氮化处理金属陶瓷刀具的磨损形态和机理

Wear morphological and mechanism of cermet tools with surface heat-treatment in nitrogen

利用真空烧结工艺和表面氮化处理工艺，制备了纳米复合Ti（C，N）基金属陶瓷可转位刀片和功能梯度Ti（C，N）基金属陶瓷可转位刀片，详细研究了氮化处理对自制金属陶瓷刀具磨损形态和机理的影响,结果表明：自制刀片氮化处理前后的磨损形态有较大不同，显示了氮化处理后，刀片表面硬度的提高和表面层合金元素的变化，使得刀片的磨损机理和切削性能发生较大变化。氮化处理刀片切削正火态45^#钢、铸铁和奥氏体不锈钢时表现出较优的耐磨性。

Nano-composite Ti（C, N）-based cermet indexable inserts and functionally gradient Ti（C, N）-based cermet indexable inserts were produced separately by vacuum sintering and surface heat-treatment with hot isostatic pressing （HIP） in nitrogen. The effect to wear morphological and mechanism of the newly fabricated cermet tools by the heat-treatment in nitrogen were investigated in detail. It was found that wear morphological of cermet tools changed after heat-treatment in nitrogen, which was due to the surface hardness being increased and the alternation of the elements in the surface layer. Comparing to the nano-composite Ti（C, N）-based cermet indexable inserts, the functionally gradient Ti（C, N）-based cermet indexable inserts exhibited a higher wear resistant for turning normalized medium carbon steel, quenched medium carbon steel and austenite stainless steel.