金属材料外文翻译关于硬质合金刀具刀刃磨损的研究文档格式.docx

1、The boundary notch of cemented carbide cutting tools is a wear area, which is relatively large, resulting from friction between main cutting edge and the surface of the workpiece as the following Fig.1. Fig.1 （a） shows a traditional wearing type of the flank. The rake face Ar and flank face Aa are a

2、lso shown. Fig.1 （b） shows the main dimension of boundary notch of the lathe tool, in which VN represented the height of boundary notch and C refers to the width. It is apparent that the greater the dimensions of VN and C are, the greater it destroys the performance of tools and influences the machi

3、ning quality3,4. By experiment, the forming process of the boundary notch can be divided into the following three steps: firstly, several micro cracks are produced at main cutting edge. Secondly, the mesh fractures are found in the boundary areas and they will spread. Finally, the piece material wil

4、l be denuded and the boundary notch is formed. In the subsequent cutting process, the dimension of the boundary becomes bigger and bigger.Fig. 2 shows the forming process of boundary notch of the cemented carbide cutting tools.Main factors to influence boundary notch are mechanical performance of th

5、e piece material, the cutter material, and geometry parameter of the cutter. The following experiments were carried out in order to expound the forming mechanism and evolution rules of the boundary notch.Fig. 1 Boundary notch of the cemented carbide cutting tool in turningFig.2 Forming process of bo

6、undary notch of the cemented carbide cutting tools.3 EXPERIMENT CONDITIONS AND TESTING MEASURES The lathe C6130 and reversible cutting tool are used in the experiment. Five cutter materials are employed. Main mechanical parameters of cutter material are shown in Table 1.The machining piece is the fr

7、iction-welded line of the single hydraulic pillar. The width of the welded line is 15mm and the machining allowance is 5.5mm. Besides, the above pillar is welded with 270SiMn and 45# steel. The relatively mechanical performances of the welded line are shown in Table 2.Based on manufacturing experien

8、ce and relative information in China and other countries about similar machining process, the chosen machining and tool geometry parameters are shown in Table 3.The boundary notch dimensions of the cemented carbide cutting tools （boundary notch height VN and width C are directly attained by tool mic

9、roscope. In order to ensure reliability of the results, repeated experiments are carried out. The recurrent performance is good.4 EXPERIMENT RESULTS AND ANALYSIS4.1 Cutter MaterialsFor different cutter materials, as shown in Fig. 3, the machining performance and the ability to resist boundary notch

10、are distinctly different.From Fig. 3, we can find the boundary notch dimensions are relatively large when YD10,YD15 and YW are used. Whereas the boundary notch dimension is smallest when YTS25 is used. Because of the asymmetry allowances impacts and vibrations will take place. YTS25 cutter has bette

11、r impact-resisting performance and boundary notch dimension. Therefore, YTS25 cutter material is selected to do the following experiments.Table 1 Material Performances of CuttersTypeMaterial PerformanceRemarkHRAb（kg/mm2）（g/cm2）YD10YD15707YW2YTS259290.59113012514515020012.4112.811.512.111.812.512.71.

12、3.312.813.2North toolsZiGongZhugongZhuzhouTable 2 Mechanical Performances of CuttersItemTensile strengthElongation rateShrinkage rateImpact toughnessb（kg/mm2）（%）Tk（kg/cm2）270SiMn1001240545#6116Welding Line64.6825.5 1337.646.23.56.4Table 3 Cutting ParametersCutting velocity V （m/min） 75Cutting depth

13、p （mm）5.5Feed rate f（mm/r）0.3Rake angle 0 （ 10Clearance angle 0 （8Cutting edge angle Kr （845 ; 75 ; 90Edge inclination s （-5Negative chamfer b1 （mm）0.1; 0.2; 0.3Cutter corner radius r（mm） 0.2; 0.4; 0.84.2 Influences of Cutting Edge AngleThe results of the variety boundary notch are shown as in Fig.

14、4 when the cutting edge angle is changed. From Fig. 4 we can find that, with the lessening of the cutting edge angle Kr , the dimensions of the boundary notch decrease. The reason is that with the lessening of the cutting edge angle Kr , the length of the cutting edge that acts on cutting becomes la

15、rger and the average loads on the cutting edge become lighter.4.3 Influences of Cutter Corner Radius rThe results of the variety boundary notch with the cutter corner changing are shown as Fig. 5.The boundary notch dimension decreases with the cutter corner radius r becoming lesser. The reason is th

16、at with the increasing of the cutter corner radius, the impact-resistance performance.Fig. 3 Different boundary notch results to different utter materialFig. 4 Influences of cutting edge angle Krincreases and the volume of the cutter that endures heat becomes larger. Therefore, under the same cuttin

17、g conditions, boundary notch dimensions （VN, C） decrease when the cutter corner radius becomes lesser.4.4 Influences of Negative Chamfer blThe experiment results of the variety boundary notch are shown as in Fig. 6 when the width of the negative chamfer is changed. The dimension of the boundary notc

18、h will decrease when the width of the negative chamfer bl decreases. Therefore, in order to resist or decrease the cutter boundary notch, the lesser negative chamfer bl should be chosen.4.5 Deburring Machining ProcessThe burrs have some influences on cutter boundary notch in metal machining process.

19、 A deburring cutter is chosen to decrease the adverse influence on cutter. A different result between deburring machining process and common machining process is shown as in Fig. 7. It can be seen that about 75% of the boundary notch is decreased. So, burr is a main factor to produce and increase th

20、e boundary notch of the cutter.Fig.5 Influence of cutter corner radius RFig.6 Influences of negative chamfer widthFig.7 Deburring machining process and common machining process5 CONCLUSIONSFrom above experimental research and theoretical analysis, the following conclusions are attained:1） Boundary n

21、otch of the cutting tool can be expressed by boundary notch height VN and boundary notch width C. The forming processes of boundary notch can be divided into three steps:micro-tipping appears firstly; Then, mesh fractures expand; Finally, boundary notch results.（2） Main factors that influence bounda

22、ry notch of cemented carbide cutter are piece material,cutter material and cutter geometry parameters.（3） Deburring machining process and adjusting cutting tool geometry parameters （to reduce edge angle Kr and width of negative chamfer bl, to increase cutter corner radius r） can be chosen to decreas

23、e effectively boundary notch, which ensures the quality of workpiece and cutting performances of cutting tool.ACKNOWLEDGEMENTSThe authors are grateful to Natural Science Foundation of P.R.C. for support of this project（Grant No. 59775071 and 50275066）.REFERENCES1 WANG Guicheng. Inner Stress in the S

24、urface of Brazed Cemented Carbide Cutting Tool.Cemented Carbide.1989,6（4）:p.169172（in Chinese）2 WANG Guicheng. Cutting Performances of Brazed Cemented Carbide Cutting Tool. Cemented Carbide. 1993, 10（1）:p.6972（in Chinese）3 ZHOU Zehua. The Principles of Metal Cutting. Shanghai: Shanghai Science and Technology Press,1985（in Chinese）4 ZHANG Youzhen. Metal Cutting Theory. Beijing: Aviation Industry Press, 998（in Chinese）关于硬质合金刀具刀刃磨损的研究摘要 硬质合金刀具的性能直接影响到工件的切削质量。在这篇文章里，研究了刀具磨损的形成机制，分析相关理论，提出了刀具磨损尺寸的定义，并且指出了刀具磨损的主要因素。除硬质合金刀具的形成过程和变动位置以外发现, 并且一定数量的措施减少和控制硬质合金刀具被推进了。关键词 刀刃磨损；硬质合金刀