涂层刀具铣削粉末冶金镍基高温合金试验研究

采用涂层硬质合金刀具进行了粉末冶金镍基高温合金的铣削刀具磨损试验,并运用扫描电镜和能谱分析技术分析了刀具的磨、破损形态和磨损机理.采用多因素正交试验对粉末冶金镍基高温合金的铣削力、刀具寿命进行研究,使用最小二乘法等方法和回归分析建立了铣削力、刀具寿命的经验模型.利用等寿命-效率响应曲面法,对干铣粉末冶金镍基高温合金的切削参数进行了优化.结果表明:粘结磨损和磨粒磨损是主要的磨损机理;在不同的切削速度下刀具失效形式不同;建立的铣削力及刀具寿命经验模型高度显著,进给量对铣削力和刀具寿命的影响显著;干铣加工粉末冶金镍基高温合金理想的切削用量为切削速度40~60m/min、轴向切削深度0.15~0.20mm、径向切削深度10~20mm、每齿进给量0.08~0.10mm.

Experimental Investigation into Milling of Nickel-Based Powder Metallurgy Superalloy with Coated Tools

Nickel-base powder metallurgy superalloy is regarded as one of the most important aerospace industry materials. Experiments of tool wear resistance were conducted using coated carbide tools for this kind of difficult-to-machining material. Then, the tool wear morphologies and mechanism were examined by SEM and EDS. Cutting forces and tool life tests were carried out which were synthesized by orthogonal test design. Cutting factors collected from the experiment are examined by using both statistic analysis and regression analysis. The models of cutting force and tool life are validated by the optimization of cutting parameters. Finally, the cutting parameters of coated carbide in nickel-powder metallurgy superalloy dry milling were optimized based on tool life-efficiency contour analysis.