Abstract A Si3N4/(W, Ti)C graded nano-composite ceramic tool was fabricated and its performance in high speed turning iron-based alloys GH2132 was investigated compared with homogeneous and commercial ceramic tools. The chip morphology, cutting forces, cutting temperature, tool life and failure mechanisms and machined surface roughness were recorded and analyzed. The results showed that with the increasing cutting speed the resultant cutting force shows a tendency to first increase and then decrease while the cutting temperature increases gradually. Straight continuous chips, bending continuous chips, twist continuous chips and snarled chips form in turn. Saw-tooth chips tend to form when the cutting speed is more than 200 m/min. The graded tool shows longer tool life especially at the cutting speed of 150 and 200 m/min compared with the homogenous and commercial ceramic tools. Tool failure modes mainly include grooving on the rake face, notching on the flank face, abrasion and adhesion. The grooving on the rake face tends to decrease while notching on the flank face tends to increase as cutting speed increases. Surface roughness of the machined iron-based super-alloys is relatively high due to the serious adhesion. Better surface roughness can be got using the graded tool.

中文翻译：

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Si 3 N 4 /(W, Ti)C梯度陶瓷刀具在高速车削铁基高温合金中的性能

摘要 制备了一种Si3N4/(W,Ti)C 梯度纳米复合陶瓷刀具，并与均质和商用陶瓷刀具进行了比较，研究了其在高速车削铁基合金GH2132 中的性能。记录和分析切屑形态、切削力、切削温度、刀具寿命和失效机制以及加工表面粗糙度。结果表明，随着切削速度的增加，切削合成力呈先增大后减小的趋势，切削温度逐渐升高。直线连续切屑、弯曲连续切屑、扭曲连续切屑和扭结切屑依次形成。当切削速度超过 200 m/min 时，往往会形成锯齿状切屑。与同质和商用陶瓷刀具相比，分级刀具具有更长的刀具寿命，尤其是在 150 和 200 m/min 的切削速度下。刀具失效模式主要包括前刀面切槽、后刀面切槽、磨损和粘连。随着切削速度的增加，前刀面上的凹槽趋于减少，而后刀面上的凹槽趋于增加。机加工后的铁基高温合金由于附着严重，表面粗糙度较高。使用渐变刀具可以获得更好的表面粗糙度。机加工后的铁基高温合金由于附着严重，表面粗糙度较高。使用渐变刀具可以获得更好的表面粗糙度。机加工后的铁基高温合金由于附着严重，表面粗糙度较高。使用渐变刀具可以获得更好的表面粗糙度。