基于响应面法优化增韧尼龙66切削工艺参数

Optimization of Toughened Nylon 66 Cutting Process Parameters based on Response Surface Method

为了探索切削工艺参数(切削速度、进给量和背吃刀量)对增韧尼龙66材料切削性能的影响规律,以切削力、切削温度和表面粗糙度为响应值进行单因素试验,结果表明,随着切削速度的逐渐增加,切削力逐渐降低,切削温度逐渐升高,表面粗糙度逐渐增大;随着进给量和背吃刀量的逐渐增加,切削力逐渐增大,切削温度逐渐升高,表面粗糙度逐渐增大。基于单因素研究结果,设计并进行响应面法试验方案,进一步探索切削参数间的交互作用对其切削性能的影响规律。利用Design-Expert软件建立试验因素与响应值之间的数学模型,通过方差分析,得到车削加工中影响增韧尼龙66切削力、切削温度和表面粗糙度的主次顺序分别为:进给量>背吃刀量>切削速度,切削速度>进给量>背吃刀量,切削速度>背吃刀量>进给量。以最小切削力、切削温度和表面粗糙度为目标进行切削工艺参数优化,并进行试验验证,切削力、切削温度和表面粗糙度的试验值与预测值的相对误差分别为2.69%,-1.64%,-2.88%,相对误差较小,说明模型比较准确。

In order to explore the influences of cutting process parameters(cutting speed,feed rate and depth of cut)on the cutting performance of toughened nylon 66,a single-factor test was conducted with cutting force,cutting temperature and surface roughness as response values,and the results show that with the gradual increase of cutting speed,the cutting force gradually decreases,the cutting temperature gradually increases and the surface roughness gradually increases.With the gradual increase of feed rate and depth of cut,the cutting force gradually increases,the cutting temperature gradually increases and the surface roughness gradually increases.Based on the results of the single-factor study,a response surface method test program was designed and conducted to further explore the influences of the interaction between cutting parameters on their cutting performance.The mathematical model between the test factors and the response values was established by using Design-Expert software.Through variance analysis,the primary and secondary order of the effects of cutting force,cutting temperature and surface roughness of toughened nylon 66 in turning machining were obtained as follows:feed rate>depth of cut>cutting speed,cutting speed>feed rate>depth of cut,cutting speed>depth of cut>feed rate.The cutting process parameters were optimized with the objectives of minimum cutting force,cutting temperature and surface roughness,and were verified experimentally.The relative errors of the experimental and predicted values of cutting force,cutting temperature and surface roughness are 2.69%,-1.64%and-2.88%,respectively,which are relatively small and indicate that the model is more accurate.