<span style="font-family:Verdana;">A metal matrix composite constitutes a continuous metallic matrix and a </span><span style="font-family:Verdana;">discontinuous phase known as r...<span style="font-family:Verdana;">A metal matrix composite constitutes a continuous metallic matrix and a </span><span style="font-family:Verdana;">discontinuous phase known as reinforcement. The hybrid metal matrix composites</span><span style="font-family:Verdana;"> (Hmmcs) have been used to manufacture drive shafts, disc brake rotors, brake drums, connecting rods pistons, engine block cylinder liners for automotive and rail vehicle applications. The Hmmcs castings of diameter 120 mm and length 300 mm were prepared through sand mould technique following stir casting methodology. The cast components further subjected to evaluation of physical properties and machining tests using two grades of coated inserts and PCD inserts. The experiments were carried out following ISO 3685 standards. The coating thickness of the TiN coated and TiAlN coated inserts were measured using Kalo testing method</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">;</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> the results of the test show that the interface of the substrate and coating was free from the porosity, and the coating thickness of TiN coating was 4.84 microns and TiAlN coating was measured 4.6 microns. The results of the experiments show that performance of the PCD insert was better than coated inserts at 0.1 mm/rev feed</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">;</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> however at 0.2 mm/revolution feed PCD insert failed by micro chipping of cutting edge while machining Hmmcs. When TiAlN coated inserts were used to machine Hmmcs the coated inserts failed by gradual wear and BUE formation.展开更多
The wear of cutting tools in the machining of 2024Al alloy composites reinforced with Al2O3 particles using varying sizes and volume fractions of particles up to 23.3vol% was investigated by a turning process using co...The wear of cutting tools in the machining of 2024Al alloy composites reinforced with Al2O3 particles using varying sizes and volume fractions of particles up to 23.3vol% was investigated by a turning process using coated carbide tools K10 and TP30 at different cut- ting speeds. Machining tests were performed with a plan of experiments based on the Taguchi method. The tool life model was developed in terms of cutting speed, size, and volume fraction of particles by multiple linear regressions. The analysis of variance （ANOVA） was also employed to carry out the effects of these parameters on the cutting tool life. The test results show that the tool life decreases with the increase of cutting speed for both cutting tools K10 and TP30, and the tool life of the K10 tool is significantly longer than that of the TP30 tool. For the tool life, cutting speed is found to be the most effective factor followed by particle content and particle size, respectively. The predicted tool life of cutting tools is found to be in very good agreement with the experimentally observed ones.展开更多
In this paper, for the tool wear problem of the cutting process, the study on improving tool life has been done through the analysis of the Seebeck effect in the efficient turning process. The generation principle of ...In this paper, for the tool wear problem of the cutting process, the study on improving tool life has been done through the analysis of the Seebeck effect in the efficient turning process. The generation principle of the self-excited electric current in the cutting process is studied, and also its effect on the life of the turning cutter is studied, so as to reveal the mechanism of the self-excited electric current accelerating the wear of cutting tools. The study results show that the self-excited electric current which is generated during the cutting process is one of the main reasons that cause both the accelerated hardening and the low life of cutting tools to happen. Thus, if the generation of self-excited current is avoided and reduced, the cutting performance of cutting tools can be effectively improved, so to improve the tool life. The study can provide the anti-friction and anti-wear theory basis for the design of the efficient cutting tools.展开更多
The requirements of high quality machined surface as well as demand of enhanced contact time of cutting tools drive towards adopting multilayer coated carbide inserts. The industry requires higher productivity, hence ...The requirements of high quality machined surface as well as demand of enhanced contact time of cutting tools drive towards adopting multilayer coated carbide inserts. The industry requires higher productivity, hence higher machining parameters need to be used in order to meet the industry requirements. The alloy steel material used to fabricate machine parts consists of alloying elements like nickel, chromium and molybdenum difficult to machine, since the cutting tool fails by high tool wear, if we use uncoated carbide inserts to machine alloy steels. Hence in the present research work it is intended to use tungsten carbide inserts coated with different coatings for the experiments. The turning experiments were carried out using different grades of uncoated and coated carbide inserts of identical tool signature. The cutting speed selected for the experiments was 100 to 500 m/min in steps of 100 m/min, and the feed per revolution was 0.1 mm to 0.4 mm in step of 0.1 mm. The experimentation was carried out following ISO3685 standards. The results of the experiments revealed that the surface roughness measured was the least at cutting speed 500 m/min and feed per revolution of 0.1 mm, however the chip breaking found better when the feed used was greater than 0.2 mm/revolution.展开更多
Short tool life and rapid tool wear in micromachining of hard-to-machine materials remain a barrier to the process being economically viable. In this study, standard procedures and conditions set by the ISO for tool l...Short tool life and rapid tool wear in micromachining of hard-to-machine materials remain a barrier to the process being economically viable. In this study, standard procedures and conditions set by the ISO for tool life testing in milling were used to analyze the wear of tungsten carbide micro-end-milling tools through slot milling conducted on titanium alloy Ti-6 Al-4 V. Tool wear was characterized by flank wear rate,cutting-edge radius change, and tool volumetric change. The effect of machining parameters, such as cutting speed and feedrate, on tool wear was investigated with reference to surface roughness and geometric accuracy of the finished workpiece. Experimental data indicate different modes of tool wear throughout machining, where nonuniform flank wear and abrasive wear are the dominant wear modes. High cutting speed and low feedrate can reduce the tool wear rate and improve the tool life during micromachining.However, the low feedrate enhances the plowing effect on the cutting zone, resulting in reduced surface quality and leading to burr formation and premature tool failure. This study concludes with a proposal of tool rejection criteria for micro-milling of Ti-6 Al-4 V.展开更多
The wear forms and reasons of PCBN tools when dry-cutting bearing steel GCr15are studied systematically. The effect law of the workpiece hardness on PCBN tools is gained andtool wearing with the quickest speed at the ...The wear forms and reasons of PCBN tools when dry-cutting bearing steel GCr15are studied systematically. The effect law of the workpiece hardness on PCBN tools is gained andtool wearing with the quickest speed at the workpiece critical hardness is proved. The life equationat two kinds of workpiece hardness demonstrates that the effect of the cutting speed on the PCBNtool life is less than that of carbide tools and ceramic tools.展开更多
Dry hobbing has received extensive attention for its environmentally friendly processing pattern.Due to the absence of lubricants,hobbing process is highly dependent on process parameters combination since using unrea...Dry hobbing has received extensive attention for its environmentally friendly processing pattern.Due to the absence of lubricants,hobbing process is highly dependent on process parameters combination since using unreasonable parameters tends to affect the machining performance.Besides,the consideration of tool life is frequently ignored in gear hobbing.Thus,to settle the above issues,a multiobjective parameters decision approach considering tool life is developed.Firstly,detailed quantitative analysis between process parameters and hobbing performance,i.e.,machining time,production cost and tool life is introduced.Secondly,a multi-objective parameters decision-making model is constructed in search for optimum cutting parameters(cutting velocity v,axial feed rate f_(a))and hob parameters(hob diameter d_(0),threads z_(0)).Thirdly,a novel algorithm named multi-objective multi-verse optimizer(MOMVO)is utilized to solve the presented model.A case study is exhibited to show the feasibility and reliability of the proposed approach.The results reveal that(i)a balance can be achieved among machining time,production cost and tool life via appropriate process parameters determination;(ii)optimizing cutting parameters and hob parameters simultaneously contributes to optimal objectives;(iii)considering tool life provides usage precautions support and process parameters guidance for practical machining.展开更多
The present study focused on mathematical modeling, multi response optimization, tool life, and eco- nomical analysis in finish hard turning of AISI D2 steel （（55 4- 1） HRC） using CVD-coated carbide （TiN/TiCN/ A1...The present study focused on mathematical modeling, multi response optimization, tool life, and eco- nomical analysis in finish hard turning of AISI D2 steel （（55 4- 1） HRC） using CVD-coated carbide （TiN/TiCN/ A1203） and uncoated carbide inserts under dry environ- mental conditions. Regression methodology and the grey relational approach were implemented for modeling and multi-response optimization, respectively. Comparative economic statistics were carried out for both inserts, and the adequacy of the correlation model was verified. The experimental and predicted values for all responses were very close to each other, implying the significance of the model and indicating that the correlation coefficients were close to unity. The optimal parametric combinations for A1203 coated carbide were dl-fl-v2 （depth of cut = 0.1 mm, feed = 0.04 mm/r and cutting speed = 108 m/min）, and those for the uncoated tool were dl-（0.1 mm）-fl （0.04 mm/r）-vl （63 rn/min）. The observed tool life for the coated carbide insert was 15 times higher than that for the uncoated carbide insert, considering flank wear criteria of 0.3 mm. The chip volume after machining for the coated carbide insert was 26.14 times higher than that of the uncoated carbide insert and could be better utilized for higher material removal rate. Abrasion, diffusion, notch- ing, chipping, and built-up edge have been observed to be the principal wear mechanisms for tool life estimation. Use of the coated carbide tool reduced machining costs by about 3.55 times compared to the use of the uncoated carbide insert, and provided economic benefits in hard turning.展开更多
In this paper the CNC machining of St52 was modeled using an artificial neural network(ANN)in the form of a four-layer multi-layer perceptron(MLP).The cutting parameters used in the model were cutting fluid flow,feed ...In this paper the CNC machining of St52 was modeled using an artificial neural network(ANN)in the form of a four-layer multi-layer perceptron(MLP).The cutting parameters used in the model were cutting fluid flow,feed rate,spindle speed and the depth of cut and the model output was the tool life.For obtaining more accuracy and spending less time Taguchi design of experiment(DOE)has been used and correlation between the output of the ANN and the experimental results was 96%.Further optimization process has been done by use of a genetic algorithm(GA).After optimization process tool life was increased about 8%equal to 33 min and was corroborated by experimental tests.This demonstrates that the coupling of an ANN with the GA optimization technique is a valid and useful approach to use.展开更多
Tool wear has an important influence on the residual stress distribution on the machined surface.Also,it will influence the fatigue life of finished workpiece. In this research,the hard turning process of hardened die...Tool wear has an important influence on the residual stress distribution on the machined surface.Also,it will influence the fatigue life of finished workpiece. In this research,the hard turning process of hardened die steel Cr12 MoV was studied by using PCBN tool with considering tool wear. Based on the numerical treatment of residual stress,the dispersion and distribution curves of different tool wear were fitted,and the influence mechanism of tool wear on the residual stress distribution of machined surface was analyzed.Based on the theory of fatigue mechanics and mathematical statistics,the mathematical model for difference of stress dispersion and fatigue life was established. The rotating and bending tests were carried out on the standard parts after cutting process for the workpiece. The influence of tool wear on fatigue life was revealed by fracture surface morphology and fatigue life study. The results provide theoretical support for control of residual stress and the fatigue property of the machined surface under the actual working conditions.展开更多
C-276 nickel-based alloy is a difficult-to-cut material. In high-speed machining of Hastelloy C-276, notching is a prominent failure mode due to high mechanical properties of work piece, which results in the short too...C-276 nickel-based alloy is a difficult-to-cut material. In high-speed machining of Hastelloy C-276, notching is a prominent failure mode due to high mechanical properties of work piece, which results in the short tool life and low productivity. In this paper, a newly developed Ti（C7N3）-based cermet insert manufactured by a hot-pressing method is used to machine the C-276 nickel-based alloy, and its cutting performances are studied. Based on orthogonal experiment method, the influence of cutting parameters on tool life, material removal rates and surface roughness are investigated. Experimental research results indicate that the optimal cutting condition is a cutting speed of 50 m/min, depth of cut of 0.4 mm and feed rate of 0.15 mm/r if the tool life and material removal rates are considered comprehensively. In this case, the tool life is 32 min and material removal rates are 3000 mm^3/min, which is appropriate to the rough machining. If the tool life and surface roughness are considered, the better cutting condition is a cutting speed of 75 m/min, depth of cut of 0.6 mm and feed rate of 0.1 mm/r. In this case, the surface roughness is 0.59μm. Notch wear, flank wear, chipping at the tool nose, built-up edge（BUE） and micro-cracks are found when Ti（C7N3）-based cermet insert turned Hastelloy C-276. Oxidation, adhesive, abrasive and diffusion are the wear mechanisms, which can be investigated by the observations of scanning electron microscope and energy-dispersive spectroscopy. This research will help to guide studies on the evaluation of machining parameters to further advance the productivity of nickel based alloy Hastelloy C-276 machining.展开更多
This paper advances the collection of statistical methods known as response surface methods as an effective experimental approach for describing and comparing the tool life performance capabilities of metalcutting too...This paper advances the collection of statistical methods known as response surface methods as an effective experimental approach for describing and comparing the tool life performance capabilities of metalcutting tools. Example applications presented demonstrate the versatility of the power family of transformations considered by Box and Cox (1964) in modeling tool life behavior as revealed using simple response surface designs. A comparative analysis illustrates a method to gauge the statistical significance of differences in tool life estimates computed from response surface models. Routine use of these methods in experimental tool testing is supported by their ability to produce reliable relative performance representations of competing tools in field applications.展开更多
文摘<span style="font-family:Verdana;">A metal matrix composite constitutes a continuous metallic matrix and a </span><span style="font-family:Verdana;">discontinuous phase known as reinforcement. The hybrid metal matrix composites</span><span style="font-family:Verdana;"> (Hmmcs) have been used to manufacture drive shafts, disc brake rotors, brake drums, connecting rods pistons, engine block cylinder liners for automotive and rail vehicle applications. The Hmmcs castings of diameter 120 mm and length 300 mm were prepared through sand mould technique following stir casting methodology. The cast components further subjected to evaluation of physical properties and machining tests using two grades of coated inserts and PCD inserts. The experiments were carried out following ISO 3685 standards. The coating thickness of the TiN coated and TiAlN coated inserts were measured using Kalo testing method</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">;</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> the results of the test show that the interface of the substrate and coating was free from the porosity, and the coating thickness of TiN coating was 4.84 microns and TiAlN coating was measured 4.6 microns. The results of the experiments show that performance of the PCD insert was better than coated inserts at 0.1 mm/rev feed</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;">;</span></span></span></span><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"><span style="font-family:Verdana;"> however at 0.2 mm/revolution feed PCD insert failed by micro chipping of cutting edge while machining Hmmcs. When TiAlN coated inserts were used to machine Hmmcs the coated inserts failed by gradual wear and BUE formation.
文摘The wear of cutting tools in the machining of 2024Al alloy composites reinforced with Al2O3 particles using varying sizes and volume fractions of particles up to 23.3vol% was investigated by a turning process using coated carbide tools K10 and TP30 at different cut- ting speeds. Machining tests were performed with a plan of experiments based on the Taguchi method. The tool life model was developed in terms of cutting speed, size, and volume fraction of particles by multiple linear regressions. The analysis of variance （ANOVA） was also employed to carry out the effects of these parameters on the cutting tool life. The test results show that the tool life decreases with the increase of cutting speed for both cutting tools K10 and TP30, and the tool life of the K10 tool is significantly longer than that of the TP30 tool. For the tool life, cutting speed is found to be the most effective factor followed by particle content and particle size, respectively. The predicted tool life of cutting tools is found to be in very good agreement with the experimentally observed ones.
基金Sponsored by the National Natural Science Foundation of China (Grant No. 51075108,51205095)the Key Project of Chinese Ministry of Education(Grant No.209034)+1 种基金the Natural Science Foundation of Heilongjiang Province (Grant No. E200919)the Support Program for Key Youth (GrantNo. 1154G39)
文摘In this paper, for the tool wear problem of the cutting process, the study on improving tool life has been done through the analysis of the Seebeck effect in the efficient turning process. The generation principle of the self-excited electric current in the cutting process is studied, and also its effect on the life of the turning cutter is studied, so as to reveal the mechanism of the self-excited electric current accelerating the wear of cutting tools. The study results show that the self-excited electric current which is generated during the cutting process is one of the main reasons that cause both the accelerated hardening and the low life of cutting tools to happen. Thus, if the generation of self-excited current is avoided and reduced, the cutting performance of cutting tools can be effectively improved, so to improve the tool life. The study can provide the anti-friction and anti-wear theory basis for the design of the efficient cutting tools.
文摘The requirements of high quality machined surface as well as demand of enhanced contact time of cutting tools drive towards adopting multilayer coated carbide inserts. The industry requires higher productivity, hence higher machining parameters need to be used in order to meet the industry requirements. The alloy steel material used to fabricate machine parts consists of alloying elements like nickel, chromium and molybdenum difficult to machine, since the cutting tool fails by high tool wear, if we use uncoated carbide inserts to machine alloy steels. Hence in the present research work it is intended to use tungsten carbide inserts coated with different coatings for the experiments. The turning experiments were carried out using different grades of uncoated and coated carbide inserts of identical tool signature. The cutting speed selected for the experiments was 100 to 500 m/min in steps of 100 m/min, and the feed per revolution was 0.1 mm to 0.4 mm in step of 0.1 mm. The experimentation was carried out following ISO3685 standards. The results of the experiments revealed that the surface roughness measured was the least at cutting speed 500 m/min and feed per revolution of 0.1 mm, however the chip breaking found better when the feed used was greater than 0.2 mm/revolution.
基金the Engineering and Physical Sciences Research Council (EP/M020657/1) for the support for this work
文摘Short tool life and rapid tool wear in micromachining of hard-to-machine materials remain a barrier to the process being economically viable. In this study, standard procedures and conditions set by the ISO for tool life testing in milling were used to analyze the wear of tungsten carbide micro-end-milling tools through slot milling conducted on titanium alloy Ti-6 Al-4 V. Tool wear was characterized by flank wear rate,cutting-edge radius change, and tool volumetric change. The effect of machining parameters, such as cutting speed and feedrate, on tool wear was investigated with reference to surface roughness and geometric accuracy of the finished workpiece. Experimental data indicate different modes of tool wear throughout machining, where nonuniform flank wear and abrasive wear are the dominant wear modes. High cutting speed and low feedrate can reduce the tool wear rate and improve the tool life during micromachining.However, the low feedrate enhances the plowing effect on the cutting zone, resulting in reduced surface quality and leading to burr formation and premature tool failure. This study concludes with a proposal of tool rejection criteria for micro-milling of Ti-6 Al-4 V.
基金This project is supported by Provincial Natural Science Foundation of China(No.59975026).
文摘The wear forms and reasons of PCBN tools when dry-cutting bearing steel GCr15are studied systematically. The effect law of the workpiece hardness on PCBN tools is gained andtool wearing with the quickest speed at the workpiece critical hardness is proved. The life equationat two kinds of workpiece hardness demonstrates that the effect of the cutting speed on the PCBNtool life is less than that of carbide tools and ceramic tools.
基金supported by the Key Projects of Strategic Scientific and Technological Innovation Cooperation of National Key Research and Development Program of China(Grant No.2020YFE0201000).
文摘Dry hobbing has received extensive attention for its environmentally friendly processing pattern.Due to the absence of lubricants,hobbing process is highly dependent on process parameters combination since using unreasonable parameters tends to affect the machining performance.Besides,the consideration of tool life is frequently ignored in gear hobbing.Thus,to settle the above issues,a multiobjective parameters decision approach considering tool life is developed.Firstly,detailed quantitative analysis between process parameters and hobbing performance,i.e.,machining time,production cost and tool life is introduced.Secondly,a multi-objective parameters decision-making model is constructed in search for optimum cutting parameters(cutting velocity v,axial feed rate f_(a))and hob parameters(hob diameter d_(0),threads z_(0)).Thirdly,a novel algorithm named multi-objective multi-verse optimizer(MOMVO)is utilized to solve the presented model.A case study is exhibited to show the feasibility and reliability of the proposed approach.The results reveal that(i)a balance can be achieved among machining time,production cost and tool life via appropriate process parameters determination;(ii)optimizing cutting parameters and hob parameters simultaneously contributes to optimal objectives;(iii)considering tool life provides usage precautions support and process parameters guidance for practical machining.
文摘The present study focused on mathematical modeling, multi response optimization, tool life, and eco- nomical analysis in finish hard turning of AISI D2 steel （（55 4- 1） HRC） using CVD-coated carbide （TiN/TiCN/ A1203） and uncoated carbide inserts under dry environ- mental conditions. Regression methodology and the grey relational approach were implemented for modeling and multi-response optimization, respectively. Comparative economic statistics were carried out for both inserts, and the adequacy of the correlation model was verified. The experimental and predicted values for all responses were very close to each other, implying the significance of the model and indicating that the correlation coefficients were close to unity. The optimal parametric combinations for A1203 coated carbide were dl-fl-v2 （depth of cut = 0.1 mm, feed = 0.04 mm/r and cutting speed = 108 m/min）, and those for the uncoated tool were dl-（0.1 mm）-fl （0.04 mm/r）-vl （63 rn/min）. The observed tool life for the coated carbide insert was 15 times higher than that for the uncoated carbide insert, considering flank wear criteria of 0.3 mm. The chip volume after machining for the coated carbide insert was 26.14 times higher than that of the uncoated carbide insert and could be better utilized for higher material removal rate. Abrasion, diffusion, notch- ing, chipping, and built-up edge have been observed to be the principal wear mechanisms for tool life estimation. Use of the coated carbide tool reduced machining costs by about 3.55 times compared to the use of the uncoated carbide insert, and provided economic benefits in hard turning.
文摘In this paper the CNC machining of St52 was modeled using an artificial neural network(ANN)in the form of a four-layer multi-layer perceptron(MLP).The cutting parameters used in the model were cutting fluid flow,feed rate,spindle speed and the depth of cut and the model output was the tool life.For obtaining more accuracy and spending less time Taguchi design of experiment(DOE)has been used and correlation between the output of the ANN and the experimental results was 96%.Further optimization process has been done by use of a genetic algorithm(GA).After optimization process tool life was increased about 8%equal to 33 min and was corroborated by experimental tests.This demonstrates that the coupling of an ANN with the GA optimization technique is a valid and useful approach to use.
基金Sponsored by the National Natural Science Foundation of China(Grant No.51575147)the Science Funds for the Young Innovative Talents of HUST(Grant No.201507)
文摘Tool wear has an important influence on the residual stress distribution on the machined surface.Also,it will influence the fatigue life of finished workpiece. In this research,the hard turning process of hardened die steel Cr12 MoV was studied by using PCBN tool with considering tool wear. Based on the numerical treatment of residual stress,the dispersion and distribution curves of different tool wear were fitted,and the influence mechanism of tool wear on the residual stress distribution of machined surface was analyzed.Based on the theory of fatigue mechanics and mathematical statistics,the mathematical model for difference of stress dispersion and fatigue life was established. The rotating and bending tests were carried out on the standard parts after cutting process for the workpiece. The influence of tool wear on fatigue life was revealed by fracture surface morphology and fatigue life study. The results provide theoretical support for control of residual stress and the fatigue property of the machined surface under the actual working conditions.
基金Supported by Program for New Century Excellent Talents in University of China(Grant No.NCET-13-0357)Shandong Provincial Natural Science Foundation of China(Grant No.ZR2014EEM026)Tai Shan Scholar Foundation of China
文摘C-276 nickel-based alloy is a difficult-to-cut material. In high-speed machining of Hastelloy C-276, notching is a prominent failure mode due to high mechanical properties of work piece, which results in the short tool life and low productivity. In this paper, a newly developed Ti（C7N3）-based cermet insert manufactured by a hot-pressing method is used to machine the C-276 nickel-based alloy, and its cutting performances are studied. Based on orthogonal experiment method, the influence of cutting parameters on tool life, material removal rates and surface roughness are investigated. Experimental research results indicate that the optimal cutting condition is a cutting speed of 50 m/min, depth of cut of 0.4 mm and feed rate of 0.15 mm/r if the tool life and material removal rates are considered comprehensively. In this case, the tool life is 32 min and material removal rates are 3000 mm^3/min, which is appropriate to the rough machining. If the tool life and surface roughness are considered, the better cutting condition is a cutting speed of 75 m/min, depth of cut of 0.6 mm and feed rate of 0.1 mm/r. In this case, the surface roughness is 0.59μm. Notch wear, flank wear, chipping at the tool nose, built-up edge（BUE） and micro-cracks are found when Ti（C7N3）-based cermet insert turned Hastelloy C-276. Oxidation, adhesive, abrasive and diffusion are the wear mechanisms, which can be investigated by the observations of scanning electron microscope and energy-dispersive spectroscopy. This research will help to guide studies on the evaluation of machining parameters to further advance the productivity of nickel based alloy Hastelloy C-276 machining.
文摘This paper advances the collection of statistical methods known as response surface methods as an effective experimental approach for describing and comparing the tool life performance capabilities of metalcutting tools. Example applications presented demonstrate the versatility of the power family of transformations considered by Box and Cox (1964) in modeling tool life behavior as revealed using simple response surface designs. A comparative analysis illustrates a method to gauge the statistical significance of differences in tool life estimates computed from response surface models. Routine use of these methods in experimental tool testing is supported by their ability to produce reliable relative performance representations of competing tools in field applications.
