PCBN刀具切削GH4169试验及仿真研究

发布时间：2018-03-31 17:41

本文选题：GH4169　切入点：PCBN刀具　出处：《哈尔滨理工大学》2016年硕士论文

【摘要】：镍基高温合金GH4169是典型的难加工材料,切削加工中材料的塑性变形引起的塑性侧流现象对已加工表面粗糙度、刀具使用性能及寿命等都有较大影响,PCBN作为一种超硬刀具在加工高温合金方面具有较大潜能,因此通过研究切削参数及PCBN刀具几何参数对加工高温合金产生的影响,对推进PCBN刀具的应用具有重要的意义,本文通过PCBN刀具直角自由切削镍基高温合金GH4169,探究切削参数、PCBN负倒棱角度和切屑形成及其影响因素对切削力及表面粗糙度的影响规律。首先,进行PCBN刀具直角切削镍基高温合金GH4169试验,通过几何参数刀具单因素试验分析出负倒棱角度影响切削力的变化关系。根据正交试验利用极差、方差分析获取切削参数对切削力的影响规律,基于试验结果进行多元线性回归分析,建立切削力经验预测模型。其次,重点对切削过程中切屑侧流现象进行研究,分析切屑侧流的影响因素及切屑侧流的产生对刀具磨损的影响,研究发现:切屑宽度增加与进给量及负倒棱角度增加成正比,与切削速度增加成反比,切屑宽度增加越多,切屑侧流也就越明显,毛刺尺寸也就越大。探究切削参数对切屑宏观形态和切屑微观形态(切屑厚度、齿高和齿间角)的影响规律。然后,根据单因素试验的数据结果,建立表面粗糙度的二阶响应曲面预测模型,对切削参数因素及交互作用进行响应曲面分析,根据试验数据验证了系统预测的误差在9%以内,具有一定的精度,以表面粗糙度为加工目标,进行加工工艺优化,来实现提高运行效率、降低生产成本的目的。最后,利用Third Wave Advant Edge有限元仿真软件,对镍基高温合金GH4169切削过程微观塑性变形进行仿真,分析负倒棱角度、切削参数变化对切削温度、切屑形态、等效应力及剪切角的影响规律,并通过塑性应变速率等指标反映材料金属在切削中塑性侧流现象。
[Abstract]:Nickel base superalloy (GH4169) is a typical difficult to be machined material. The plastic side flow caused by plastic deformation of the material in cutting process has a good effect on the roughness of the machined surface.As a super hard tool, PCBNs have great potential in machining superalloys. Therefore, the effects of cutting parameters and PCBN tool geometry parameters on the processing of superalloys are studied.It is of great significance to advance the application of PCBN cutting tools. In this paper, the cutting parameters, negative chamfering angle, chip formation and their influence factors on cutting force and surface roughness are investigated by PCBN tool free cutting of Ni-base superalloy GH4169 at right angle.First of all, the GH4169 test of cutting nickel base superalloy with PCBN tool at right angle was carried out. The change of cutting force was analyzed by single factor test of geometric parameter cutting tool.The influence of cutting parameters on cutting force was obtained by means of range and variance analysis in orthogonal experiments. Based on the experimental results, a multivariate linear regression analysis was carried out, and an empirical prediction model of cutting force was established.Secondly, the phenomenon of chip side flow in cutting process is studied. The influence factors of chip side flow and the influence of chip side flow on tool wear are analyzed. It is found that the increase of chip width is directly proportional to the increase of feed rate and negative inverted angle.The more the chip width increases, the more obvious the chip side flow is and the bigger the burr size is, the inversely proportional to the cutting speed.The effects of cutting parameters on chip macro morphology and chip micro morphology (chip thickness, tooth height and angle between teeth) were investigated.Then, according to the data of single factor test, the second order response surface prediction model of surface roughness is established, and the response surface analysis of cutting parameters and interaction is carried out. According to the experimental data, the error of the system prediction is less than 9%.It has certain precision, takes the surface roughness as the processing target, carries on the processing craft optimization, to achieve the purpose of improving the operation efficiency and reducing the production cost.Finally, Third Wave Advant Edge finite element simulation software is used to simulate the micro-plastic deformation in the process of GH4169 cutting of Ni-base superalloy. The negative inverted angle, the change of cutting parameters to the cutting temperature and chip shape are analyzed.The effect of equivalent stress and shear angle on the plastic lateral flow in cutting is reflected by plastic strain rate.
【学位授予单位】：哈尔滨理工大学
【学位级别】：硕士
【学位授予年份】：2016
【分类号】：TG506

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