TC4钛合金高速铣削加工刀具失效机理研究

2019-08-30

作者：罗学全，于涛，蒋双双，江爱胜单位：株洲钻石切削刀具股份有限公司

摘要：以TC4钛合金为试验材料，采用超细硬质合金PVD涂层刀具进行高速铣削加工，研究刀具在铣削TC4材料时的失效机理。试验通过采用扫描电子显微镜（SEM）和元素能谱检测（EDS），分别对失效刀具的刃口区域、前刀面区域、后刀面区域的磨损进行失效形貌检测和合金元素成分的分析测试。研究表明：超细晶粒硬质合金PVD涂层刀具进行TC4钛合金高速铣削加工时，刀具的失效形式在不同加工区域各有不同，刃口以黏结磨损失效和热—机械疲劳磨损失效为主，前刀面和后刀面以黏结磨损失效为主，刃口的热—机械疲劳裂纹扩展到前刀面和后刀面，并加剧了刀具的崩缺失效。

关键词：超细硬质合金；钛合金；TC4；铣削加工；失效机理

中图分类号：TG707；TH161文献标志码：ADOI：10.3969/j.issn.1000-7008.2019.09.010

Study on Failure Mechanism of Tool for High Speed Milling TC4 Titanium Alloy

Luo Xuequan，Yu Tao，Jiang Shuangshuang，Jiang Aisheng

Abstract:In this paper，titanium alloy TC4 is used as the test material，and the high speed milling mechanism of ultrafine cemented carbide PVD tools is used to study the failure mechanism of the tool when milling of TC4 material.Scanning Electron Microscopy (SEM) and Energy Dispersive Spectrometer (EDS) are used to detect the failure morphology and analytical testing of elemental composition of the cuttingedge area，rake face area，flank area damage of the failed tools.The results show that when the ultrafine cemented carbide PVD cutter is used to high speed milling the titanium alloy TC4，the failure mechanism of the cutter is different at different positions.The cutting edge is mainly caused by bond wear failure and thermalmechanical fatigue wear failure.The rake face and the flank face are mainly caused by bond wear failure.The thermalmechanical fatigue crack of the cutting edge extends to the rake face and the flank face，which aggravates the tool collapse failure.

Keywords:ultrafine cemented carbide；titanium alloy；TC4；milling；failure mechanism