外文翻译---关于工艺参数对热挤压镁合金影响的研究(编辑修改稿)

外文翻译---关于工艺参数对热挤压镁合金影响的研究(编辑修改稿)内容摘要：

(11) where Ao represents the crosssectional area of the billets and Af is the crosssectional area of the final product. This study involves direct hot extrusion processing. The preprocess involves putting the lubricant on the die and the billets, and then putting them in a furnace to be heated. The container is simultaneously preheated for h, before extrusion forming. . Experimental planning of L9 orthogonal array Before the planning orthogonal array (OA) can be implemented, trial and error is applied to determine the control factors of the hot extrusion. This method seeks the levels of the control factor during hot extrusion. Its factor level is set as shown in Table 2, and the final extrusion speed is 1 mm/s. Billets of AZ31 and AZ61 关于工艺参数对热挤压镁合金影响的研究 5 magnesium alloy are the outer OA, and the control factors of the inner OA are billet heating temperature, initial extrusion speed, container temperature and lubricant, each control factor has three levels. Their innerOAis an L9 orthogonal array, and the orthogonal array is set as shown in Table 3. . Test of mechanical properties The tube flattening test, as specified by CNS 13868 (JIS H4090), is used for piece is cut from the tube, which is then pressed between the two plates of a testing machine that weighs 30 tonnes. The welded zone is placed at the position of the pressing direction, where it forms a perpendicular angle. During the flattening test, the flattening speed is mm/min. When the plates are at H= D, the wall of the tube is observed to identify any breaking or cracking. The tensile test is performed according to specifications CNS 2111 and CNS 2112, with a tensile speed of mm/min. 4. Results and discussion The magnesium alloys used in this study are AZ31 and AZ61, which are used to carry out hot extrusion into a tube with a thickness of 2 mm. The final of the experiment based on the orthogonal array was performed must then undergo tensile and flattening tests, to understand the mechanical properties of the tube. Also, the tensile strength from the tensile test was analyzed by measuring the quality characteristics and by performing ANOVA, to determine the optimal bination of process parameters and the importance of each factor. Finally, a confirmatory experiment is performed to verify its accuracy. . Analysis of flattening test The flattening test is conducted with reference to the relevant specifications. When the distance between the two plates is H= 30 mm, the wall of the tube is examined to see whether any breaking or cracking has occurred. Table 4 shows that when H= 30 mm, no breaking is observed in the tubes made from two set of billets AZ31 and AZ61, the bearable loading of the AZ31 tube is between and N, and the bearable loading of AZ61 is and N. When theflattening test is continued until the tube breaks, the loading of the AZ31 tube is or above, while that of the AZ61 tube is at least N. Comparing these two sets of billets reveals that when H= 30mm and they start to break, the more AZ61 tube can bear a higher loading than the AZ31 tube. . Optimal process parameters for maximizing the tensile strength of the tube Table 5 presents the results of the tensile strength experiment for the tube. This results in this table show that the mean tensile strength of the AZ31 tubes is distributed from to , and that of the AZ61 tube is distributed from to . The tensile strengths of the AZ31 billets and the AZ61 billets before extrusion are and . The parison shows that the tube that underwent hot extrusion has a higher tensile strength. The greater tensile strength of a tube corresponds to higher quality. Therefore, the S/N ratio is calculated as a largerisbetter value, using Eq. (1), it is as indicated in Table 5. Figs. 3 and 4 show the results analyzed by the factor effect diagram that is 关于工艺参数对热挤压镁合金影响的研究 6 constructed from the S/N values in Table 5. The largest S/N value from this figure yields the optimal bination of process parameters. The process parameters considered in this study are billet heating temperature, initial extrusion speed, container temperature and type of lubricant. The factor effect figure, Fig. 3,reveals that the optimal bination of process parameters for the hot extrusion of AZ31 tube is heating temperature of billet = 320 ◦C, initial speed of extrusion = 2 mm/s, container temperature = 300 ◦C and a BN lubricant The factor effect figure, Fig. 4, reveals that the optimal bination of process parameters for AZ61 tube is heating temperature of billet = 320 ◦C, initial speed of extrusion = 2 mm/s, container temperature = 350 ◦C and a graphite lubricant. In the quality property analysis of a magnesium alloy tube, the tensile strength must be considered. The extruded tube using the aforementioned optimal bination of process parameters yields a product with the。