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Ring rolling is an advanced continuous local plastic forming process seamless ring part is mainly used for the manufacture of a variety of cross-sectional shape, with low production costs, product performance and product high precision, widely used in automobiles, trains , in the field of shipbuilding, aerospace and nuclear industry. This article by finite element simulation and experiment, ring in the preliminary heat, cold rolling and quenching process of rectangular cross-section of the cold-rolled microstructure evolution and deformation behavior, ring rolling process optimization and product improve the accuracy of provide a theoretical basis. First preliminary heat treatment of 45 steel rings pieces, tensile test, the mechanical properties of the test material, to establish the constitutive relationship, and according to the the material constitutive measured in ABAQUS software to simulate the process of cold rolling ring in D56G90 changes in type of precision cold ring rolling machine rolling, heat treatment ring on the final microstructure after each step process using electronic scanning electron microscopy. The simulation and experimental studies showed that: within a certain range, the faster the annealing cooling rate of the ring member, the smaller the pearlite grains, the smaller the spacing of the sheet layers, more uniform grain size distribution, the better the strength and ductility of the material. With the annealing cooling rate is decreased, the yield strength, tensile strength, elongation, and hardness decreases. 45 steel ring member after cold rolling, the cooling rate, the larger the ring pieces the stress, the strain is smaller. Grains along the rolling direction distribution, compared with not after preliminary heat treatment of cold-rolled directly ring member, the finer the ring pieces grains treated by the annealing process, tissue distribution is more uniform, and in a preliminary heat treatment of annealing and cooling faster the ring after the cold-rolled pearlite lamellae broken more serious, less obvious grain boundaries. Preliminary heat, cold rolled, quenched the test process of GCr15 steel ring piece, cold rolling process was simulated using ABAQUS software. Electron microscopy and electron microscopy, tensile tests, x-ray diffraction and microhardness testing testing methods to observe the changes of the microstructure and mechanical properties of GCr15 steel ring pieces in the process. The results show: the GCr15 steel balls oriented after annealing, the transition from flaky pearlite granular pearlite, and mitigation with the annealing cooling rate after annealing, the cementite grains becomes large, the tensile strength increases, the elongation becomes small cold after rolling, annealing and cooling speed ring, the outer layer of {111} lt; 112 gt; texture and {111} lt; 110 gt; stronger texture. With the transition from the outer layer to the middle layer, texture gradually becomes cluttered, {111} lt; 110 gt; texture component waning, {111} lt; 112 gt; gradually increased texture components, {111) lt; 11O gt; texture to the inner layer of the transition to the {111} lt; 112 gt; texture transition, while rotating the cubic {100} lt; 011 gt; texture exist; {111} lt; 112 gt; texture {111} lt; 110 gt; texture strength somewhat weaker and weaker rotation cubic {100} lt; 011 gt; texture components. After quenching, the annealing and cooling speed of the ring member, the martensite grain finer cementite particles smaller GCr15 steel ring member of the change of hardness in the entire process is, after normalizing, the ring member Hardness Change ; After annealing, the hardness decreased; after cold rolling, the hardness increased slightly; after quenching, hardness grow exponentially. After each step process, the hardness of the annealing cooling rate is slow, the highest hardness of the ring member, the hardness of the two other ring member with the annealing cooling rate of faster and smaller
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