| 69111-stainless steel (09Cr12Mn5Ni4Mo3Al) was developed by our country in 1950s, which was developed based on the resources of our country by the research center 621, 625 and the third company of Shanghai steel company and Shanghai steel research center and etc. Its performances are better than the same style steel overseas. However, 69111-stainless steel is typically hard-to-cutting material, and its application history is very short, the research about its cutting performances is little. The research status about the 69111-stainless steel is analyzed and summarized; meawhile, the cutting mechanism and process parameters optimization are focused to describe the cutting characters of 69111- stainless steel comprehensively.(1) The orthogonal tests and the single factor experiments were designed and conducted with four different kinds of tools. The experiment data was processed by the orthogonal experiment analysis method, to describe the parameters which have less effect on the cutting forces. The cutting force model was built by nonlinear fitting method, which makes the cutting force prediction become reality in theory. Tool life and tool wear experiment of the cutting 69111- stainless steel was conducted with the optimized parameters, so that the tool life and tool wear curve of the solid carbide cutting tool can be derived.(2) The surface integrity of the milled 69111- stainless steel was analyzed by the surface roughness and the residual stress. For the solid carbide cutting tool:the milled surface roughness was investigated by the orthogonal experiment analysis method to get the sequence of the parameters which influence the surface roughness. The surface roughness empirical formula was built by quadratic term nonlinear fitting method with high precision. The tensile stress was found during most of the residual stress analysis processes. For the indexable tool:the surface roughness of the milled surface using the ISCAR tool is larger than the other two tools, so its micro-structure is not fit for milling 69111- stainless steel. The residual stress of the surface milled by the SANDVIK tool took on different characters compared with the other tools. The rules of the surface roughness influenced by the parameters are shown following:the surface roughness increase larger linearly with the increasing cutting speed and the feed, while decrease linearly with the increasing axial depth-of-cut (DoC). However, there is an inflexion with the increasing radial DoC. The characters of the surface residual stress influenced by the parameters are not obvious, because the parameters have an indirect influence on the stress through affecting the milling force and the milling temperature indirectly.(3) The constitutive model and the failure model of 69111- stainless steel were built through designing the dynamic compression test and the quasi-static tensile test under different strain rates and temperatures, the tensile test under different stress tri-axiality. The friction test was designed to get the relationship between the friction coefficient, the pressureand speed.(4) The optimization of the milling parameters was accomplished based on the former research. Firstly, the geometric structure optimization of the cutting tool was completed by FEM, and the optimized rake angel, flank angel and the radius of the cutting edge give significant support to the micro-structure design of the tool. Then the optimization of the milling parameters based on the solid carbide cutting tool was completed, considering comprehensively on the milling force, the surface roughness, and the removal rate, with the orthogonal experiment analysis method and the optimized parameters increases the production efficiency. On the other hand, the optimization of the cutting speed under the situation of high speed finishing machining was completed considering the milling force and the cutting temperature, which has a guide meaning to the practical manufacturing.
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