陶瓷刀具在发动机中介机匣加工中的应用

采用陶瓷刀片进行了发动机中介机匣的粗铣切削试验,研究了陶瓷刀片加工镍基高温合金的切削性能,优化了切削参数和走刀路线,分析了高速干式加工的切屑形态,指出应用陶瓷刀具加工镍基高温合金是提高效率、降低成本的有效途径。     

镍基高温合金高速切削加工性

镍基高温合金具有优良的高温强度以及良好的热稳定性和抗热疲劳性能,广泛应用于航空发动机、燃气涡轮机等领域。但其可加工性极差,切削过程中刀具迅速磨损,加工效率较低。本文介绍了镍基高温合金高速切削加工性的研究进展,重点阐述了适宜高速切削镍基高温合金的陶瓷和PCBN刀具及加工参数,并总结了切削过程中刀具的失效形式和磨损机理,以及利用辅助加工方法等实现陶瓷刀具对镍基高温合金精加工的可能性。为高速切削镍基高温合金加工刀具的快速选择及加工工艺的改进提供了参考。     

高温合金的切削加工

我厂在试制新产品时,遇到的难加工材料有铁镍基高温合金 Incoloy901(国内称N901)、镍基高温合金 C263和钴基高温合金 Haynes—25(简称 HS—25)等,当时试用 YG8、YA6、YW2等刀片加工 N901制成的零件,均不能胜任;用813刀片也因刀片寿命短、磨损大而不能满足精车时的精度要求。为了完成     

新型切削陶瓷

<正>目前可采用热压陶瓷刀片来加工镍基超强度合金。近年来这种切削陶瓷的加工效率提高了7倍。用陶瓷短纤维强化的ACMCS-7复合材料是改进这类工具材料迈出的新的一步,这种复合材料能有效地用于灰铸铁、可锻铸铁和各种硬度的合金钢的车、铣加工。通过     

高效铣削镍基高温合金GH4169的有限元数值模拟

在DEFORM软件中,根据实际加工情况建立整体硬质合金立铣刀加工镍基高温合金GH4169的三维有限元仿真分析模型。针对镍基高温合金GH4169加工效率低和切削刃磨损严重的问题,采用单因素试验法仿真探讨了切削用量(v、f_z、a_p、a_e)对切削力和切削温度的影响规律。获得了能有效提高镍基高温合金GH4169加工效率的切削用量,为实际加工中实现高效铣削镍基高温合金切削用量的选择提供依据。     

汽雾冷却下高速切削GH4169切削力和粗糙度试验分析

本文针对陶瓷车刀片在汽雾冷却下进行切削镍基高温合金GH4169单因素试验和正交试验进行分析研究。利用最小二乘法对所得试验数据进行线性回归分析,建立切削力和已加工表面粗糙度的经验模型,分析在汽雾冷却条件下使用陶瓷刀具的切削参数对切削力和已加工表面粗糙度的影响规律。通过正交试验结果分析出最优的切削参数,为进一步优化切削参数、研究刀片磨损机理提供参考依据。     

镍基高温合金斜角切削的仿真研究

针对难加工材料镍基高温合金切削力大以及难排屑等问题,在ABAQUS有限元分析软件中建立三维斜角仿真模型,模拟镍基高温合金的切削加工过程。研究斜角切削状态下镍基高温合金材料的去除机理和切屑形成,通过正交试验和单因素试验,分析在不同切削参数下流屑角以及三维切削力的变化情况。采用有限元分析方法对镍基高温合金的三维斜角切削过程进行仿真研究,降低了研究成本,为镍基高温合金高效切削加工提供了理论参考。     

基于Deform-3D的Inconel 718镍基合金的车削仿真

Inconel 718镍基高温合金的力学、抗氧化、抗热变形的性能好,但是加工性能差,材料塑性大、导热系数低、加工硬化严重等问题制约了镍基高温合金的广泛使用.文中运用有限元软件分析和研究材料的切削性能、刀具选择以及切削参数等问题,对解决镍基高温合金难加工的现状提供了参考价值.     

镍基高温合金加工研究

简要介绍了镍基高温合金的物理性能和加工性能;进而介绍了国内外镍基高温合金切削加工的研究成果,主要分析重点集中在刀具材料的选择及切削性能的研究等方面;最后介绍了Inconel617切削加工性能和小孔加工工艺。     

陶瓷刀具的性能和实际应用技术

随着现代科技的发展，各种高强度、高硬度工程材料越来越多地被采用，这给切削加工带来了很大的困难。传统的硬质合金刀具难以胜任或根本无法实现对这类材料的加工，而陶瓷刀具有很高的耐磨性、红硬性，可以实现对多种难加工材料（淬硬钢、冷硬铸铁、镍基高温合金等）进行高速切削，生产效率比普通硬质合金刀具高３～８倍。根据我们的使用情况，对性能优越的陶瓷刀具进行分析并与普通刀具进行对比，优化了加工工艺参数。陶瓷刀具的切削性能使用Si３N４基系列的陶瓷刀具，其优点如下：①高硬度：该种刀片的室温硬度值已超过了最好的硬质合金…     

加工镍基合金时切削力和切削温度的特点

本文研究了新型陶瓷刀具ＪＸ－２－Ｉ切削基合金时切削力和切削温度的特点。结果表明，在本试验条件下，切削温度较高，而且随切削速度的提高而呈快速上升的趋势，因此在切削基合金时必须使用冷却液；由于Ｉｎｃｏｎｅｌ７１８高温强度屈服拐点的影响而存在一个切削力最小的速度范围，据此可以选取合理的切削速度。     

新型陶瓷刀具材料的耐磨损性能

研究了近几年来所研制成功的几种新型陶瓷刀具材料切削加上高强钢、高温镍基合金、淬硬钢与铸铁时的耐磨性能。结果表明:加工不同材料时刀具的耐磨损能力不同,在实际应用时可根据需要选用合适的刀具材料。     

陶瓷材料微波辅助塑性切削技术综述

介绍了国内外陶瓷材料加工方法研究概况,提出一种微波辅助切削加工陶瓷材料的新方法。该方法利用微波加热使陶瓷材料在较高温度下塑性化,从而获得到较好的加工性。介绍了微波加工试验样机的设计方案,包括微波电路图、刀具与微波天线一体化结构等。     

Performance of coated and uncoated mixed ceramic tools in hard turning process

The present contribution deals with the study of the effects of cutting speed, feed rate and depth of cut on the performance of machining which traditionally named “machinability”. The focus is made on the effect of the pre-cited cutting parameters on the evolution of surface roughness and cutting force components during hard turning of AISI D3 cold work tool steel with CC6050 and CC650 ceramic inserts. Also, for both ceramics a comparison of their wear evolution with time and its impact on the surface equality was proposed. The planning of experiments was based on Taguchi’s L₁₆ orthogonal array. The analysis of variance (ANOVA), the signal-to-noise ratio and response surface methodology (RSM) were adopted. Consequently, the validity of proposed linear regression model was checked and the most important parameter affecting the surface roughness and cutting force components were determined. Furthermore, in order to determine the levels of the cutting regime that lead to minimum surface roughness and minimum machining force the relationship between cutting factors was analyzed. The results revealed that the surface quality obtained with the coated CC6050 ceramic insert is 1.6 times better than the one obtained with uncoated CC650 ceramic insert. However, the uncoated ceramic insert was useful in reducing the machining force.     

Strategies for grinding of chamfers in cutting inserts

In order to increase tool life and improve workpiece quality, cutting processes with geometrically defined cutters demand inserts with a prepared cutting edge. Chamfers are widely used in many processes, since they can provide edge strengthening without damaging the chip flow. In order to achieve a stable and reliable cutting process, uniform chamfer geometry along the insert and high edge quality are necessary. For this, proper grinding strategies for chamfer manufacturing must be taken into account. With the objective of getting knowledge about the chamfer manufacturing process, strategies for grinding of chamfers are investigated in this paper. Chamfers were ground on PCBN, mixed ceramic and cemented carbide cutting inserts with a vitrified bond diamond grinding wheel. A single grain chip thickness model is used to characterize the process and different grinding strategies are analyzed in terms of reduction of chamfer geometry deviation. It was found that high insert rotational speeds increase the edge chipping and that the cutting insert material has a considerable influence on the chamfer geometry deviation.     

The cutting tool stresses in finish turning of hardened steel with mixed ceramic tool

Precision hard machining is an interesting topic in manufacturing die and mold, automobile parts, and scientific research. While the hard machining has benefit advantages such as short cutting cycle time, process flexibility, and low surface roughness, there are several disadvantages such as high tooling cost, need of rigid machine tool, high cutting stresses, and residual stresses. Especially, tool stresses should be understood and dealt with to achieve successful performance of finish hard turning with ceramic cutting tool. So, the influence of cutting parameters on cutting stresses during dry finish turning of hardened (52 HRC) AISI H13 hot work steel with ceramic tool is investigated in this paper. For this aim, a series finish turning tests were performed, and the cutting forces were measured in tests. After literature procedure about finite element model (FEM), FEM is established to predict cutting stresses in finish turning of hardened AISI H13 steel with Ceramic 650 grade insert. As shown, effect of the cutting parameters on cutting tool stresses in finish turning of AISI H13 steel is obtained. The suggested results are helpful for optimizing the cutting parameters and decreasing the tool failure in finish turning applications of hardened steel.     

瓷砖刮平机刮削深度建模与实验研究

为了研究瓷砖刮平机刮削效果,分析了刮平机的系统结构和工作原理,并建立了刮削深度模型。分析了影响刮削深度的因素,对所建模型进行了实验验证。理论分析和实验研究结果表明:大直径滚筒、瓷砖低速进给、较大的滚刀切削深度三者配合能有效地提高瓷砖的刮削效率。     

Use of Ceramic Tools in Hard Turning of Hardened AISI M2 Steel

Tool wear and machining performance of hardened AISI M2 steel in hard turning has been studied. Ceramic tools were used in the cutting tests without coolants, and the workpiece was heat treated to increase its hardness up to Re 60. Cutting forces, temperature, and tool wear were measured in the experiments and the effects of cutting conditions on these were investigated. Important aspects from the research are summarized as follows: 1. Flank wear was the dominant wear mode on the ceramic tool insert in hard turning. In contrast, crater wear was very small due to the ceramics high resistance against chemical reactions at high temperature. A notch was unlikely to be formed in the tool.

2. The initial flank wear rate mainly depends on the feed rate. High feed rates cause a high initial flank wear rate.

3. Depth of cut was the most important cutting parameter to affect cutting force variation, and the cutting force increased due to tool wear.

     

陶瓷刀具在大型薄壁件加工中的应用

从分析优质合金钢的薄壁件质量不合格的原因入手，结合难加工材料的高速切削机理，改进工艺流程。提出利用陶瓷刀具实现大型薄壁件高速切削的可行性，澄清了利用陶瓷刀具加工的几个误区，并对切削过程中的注意事项及切削参数的选择提出一些建议。实际使用表明在中型机床上利用陶瓷刀具可以实现大型薄壁件的高速切削，实现以车代磨，从而降低了生产成本，提高了生产效率，满足了产品的质量要求。