鑽石刀具無法切削鐵系金屬及其他過渡金屬，是因為切削加工時易使鑽石刀具產生嚴重的磨耗，其因在於鑽石與鐵金屬之間所產生的熱化學反應。近年來，已有許多研究透過電漿滲層處理含鐵原素之材料，促使基材中之鐵原子與氮原子形成FeN，進而降低鐵原子與鑽石之碳原子接觸之機會，以達到減低刀具磨耗之目的。本研究鑽石車削的實驗在下列加工參數中完成：單點鑽石刀具、切削進給1μm/rev.、切深變化(1μm、2μm與3μm)、切削距離變化(201m、188m、151m)，並使用少量的無機油當作切削液。結果顯示於相同的參數下，長距離車削經電漿氮化處理之試片可得到10nm以下的表面粗糙度。最後證實經由表面處理之鋼材所造成之刀具磨耗比無表面處理時改善許多。 本研究將不同鉻含量鋼材，STAVAX不鏽鋼、H13與SKD61工具鋼，三種材料經電漿滲氮表面處理後，經由單點鑽石車削加工，在不同鉻含量鋼材中刀具磨耗會隨鉻含量減少而有明顯降低情形。 Ferrous and other transitional metals are normally considered to be non-diamond turnable for the excessive tool wear caused by the thermal-chemical reaction between diamond and ferrous metals. In the present research, ferrous specimens were plasma nitrided at relatively low temperature to prevent the depletion of Cr content at the austenite matrix and to give a hardened layer where Fe atoms are bonded to nitrogen atom to form FexNy. Diamond turning experiments were subsequently carried out by setting cross-feed at 1μm /rev, cut-depth ranged from 1μmto 3μm, cutting distance up to around 200m, and light mineral oil as the cutting fluid. Three steel materials, namely Stavax stainless steel, H13 and SKD61 were adopted in this study for plasma nitriding and diamond turning experiments. The results showed that, better surface finish and lower tool wear were obtained on all plasma nitrided specimens in comparison to those were not treated. This means that the plasma nitriding can effectively minimize the thermal-chemical reaction between diamond tool and ferrous metal so as to suppress the tool wear and improve the achievable surface finish. Besides, amongst the nitrided steels tested there was this trend that lower Cr content showed lower wear during the diamond turning processes.
