材料期刊网

目的 研究TiAlN及TiAlSiN涂层的微观结构及力学性能,以及硬质合金涂层刀具切削SUS304不锈钢的切削性能及磨损行为.方法 采用阴极电弧离子镀技术在硬质合金试片及铣刀上分别制备纳微米TiAlN及TiAlSiN涂层.通过X射线荧光测量系统测量涂层的厚度,用扫描电镜(SEM)观察涂层表面形貌,用能谱仪(EDAX)分析涂层元素成分,用X射线衍射(XRD)分析涂层晶相结构,用纳米压痕仪表征涂层硬度,用洛氏硬度计定性测量涂层结合力,通过高速铣削试验探究涂层刀具的切削性能及磨损行为.结果 TiAlN及TiAlSiN涂层的厚度分别为3.32μm和3.35μm,表面致密、光滑,高分辨率(20000×)下观察到涂层表面有液滴、针孔及凹坑存在.Si元素促进了TiN(200)晶相的生长,晶粒尺寸减小,硬度增加.TiAlN及TiAlSiN涂层的显微硬度分别为29.6 GPa及37.7 GPa,结合力分别满足VDI-3198工业标准的HF3和HF1等级.在130 m/min的高速切削条件下,TiAlSiN涂层刀具寿命约为未涂层刀具的5倍,TiAlN涂层刀具的1.5倍.结论 Si掺杂制备的TiAlSiN涂层具有高的硬度及良好的抗粘附性,更适用于不锈钢材料的高速切削加工.

To study microstructure and mechanical property of TiAlN and TiAlSiN coatings as well as cutting performance and wear behavior of cemented carbide coated cutting tools in cutting SUS304 stainless steel. Nano-micron TiAlN and TiAlSiN coatings were prepared by cathodic arc ion plating on the surface of cemented carbide sample and milling cutter. The thickness of the coating was measured by X-ray fluorescence measurement system. Scanning electron microscopy (SEM) was used to ob-serve coating surface morphology. Energy dispersive spectroscopy (EDAX) was used to analyze coating elements; nano indenter was applied to measure the coating hardness. Rockwell Hardness Tester was implemented to investigate the adhesion strength qualitatively. High speed milling experiment was used to study the cutting performance and wear behavior of coated cutting tools. The thickness of TiAlN and TiAlSiN coatings were 3.32μm and 3.35μm respectively. The coating surface is dense and smooth. Droplets, pinholes and shallow craters existed on coating surface when observed under high resolution (20000×). The Si element promoted the growth of TiN (200) crystal phase. The grain size decreased when the hardness increased. The mi-cro-hardness of TiAlN and TiAlSiN coatings were 29.6 GPa and 37.7 GPa respectively. The adhesion strength met the VDI-3198 industrial standard of HF3 and HF1 levels. At high cutting speed of 130 m/min, the life of TiAlSiN coated tool was about 5 times than that of uncoated tool, and 1.5 times than that of TiAlN coated tool. TiAlSiN coating prepared by Si doping has higher hardness and better resistance to adhesion, which is more suitable for high speed machining of stainless steel.