Study Cutting Parameters And Surface Finish Of Hardened Steel

With the widely utilization of high speed cutting technology in the field of metal parts machining, the surface quality of the workpiece under high speed machining conditions is attracting more and more intensive attention.While the surface quality of machined metal parts has explicit effect on wear resistance, corrosion resistance, fit stability and reliability, anti-fatigue performance and service life of products.The essence of the surface formation mechanism under the condition of high speed milling can be summarized as follows:In the milling process, the periodic non-uniform stress field and temperature field of milling are coupled, acting on the elastic-plastic material surface, producing the elastic and plastic deformation on the material surface, thus affecting the processed layer of the physical and mechanical properties of workpiece geometry precision and surface modification.In the high speed cutting process,the cutting parameters and tool parameters have effects in common on machined surface integrity and the processing quality. To study the effects of tool parameters on the surface roughness and surface hardening of material processing, cutting force, we used methods of simulation and experiment study in this paper, taking Crl2MoV mold steel as the research object, studied the PCBN tool chamfer angle, focusing on the cutter negative chamfer degree on cutting force, on cutting force, and surface quality etc.. The main contents of this paper are as follows:1. Using the finite element analysis software Abaqus, established a model of milling process with single tooth for simulation. In this paper, through the numerical simulation on the single tooth milling process, introduced and determined the milling model for analysis, such as the constitutive model of the material, material separation criterion, the friction characteristics of tool chip contact and the mesh size, and introduced the steps of cutting simulation prodess in detail. Under the single factor condition the changing of the cutting speed, axial depth of cutting, and the tool chamfer angle on the milling force in the cutting process were analysed.2. Determined the high speed milling experiment scheme.The HAAS five axis CNC machining center was used to carry out the experiment scheme. In the experiment, selected the tools with different chamfer angles, and used the different milling process parameters for milling of hardened die steel Crl2MoV, according to single factor experiment method. Processed analysis on the cutting force signal data obtained with BUAA dynamometer. Obtained the influence trend of the milling parameters and tool chamfer angle on cutting force. And experimental results were compared with the simulation results, to verify reasonability of principle obtained.3.Used the J-C surface roughness measuring instrument to measure the finish of machined surface. Analyzed the changing tendency of the effects of the single factor conditions such as the spindle speed, axial depth of cutting, feed rate, and the negative chamfer of cutting tool on the machined surface.4. Used the MVC-1000A1micro hardness tester to measure the Victorinox micro hardness of the machined surface. Analyzing the changing law of the effects of the single factor condition such as the spindle speed, axial depth of cutting, feed rate,and the negative chamfer of cutting tool on the machined surface Victorinox microhardness.