ZnAl33合金轧制工艺与组织性能研究-材料加工工程专业论文.docxVIP

哈尔滨工业大学硕士论文 哈尔滨工业大学硕士论文 万方数据 万方数据 Abstract Zinc and zinc alloy has good decay resistance, excellent wear resistance and appropriate mechanical property, what makes zinc alloy are very attractive in sliding frictional part. Now zinc alloy often used as the cast, but it always has low ductility and toughness, plastic deformation can improve the ductility of cast. In this paper, study on microstructure and properties of different rolling processes of ZnAl33 alloy, in order to explore rules of rolling technology of zinc alloy. At first, cast plate was rolled with 15%, 20%, 25%, 30% thickness reduction by multi-pass rolling process until 4mm. The results said that, rolled plate has much higher ductility-but lower strength compared with the case one. With the increase of thickness reduction, tensile strength improved continuously, however ductility and yield strength fluctuates smoothly. The plate rolled with 25% thickness reduction has the highest tensile strength while the 15% highest elongation. Plate under 30% show highest comprehensive property, with tensile strength of 268MPa, elongation of 23.5%, friction coefficient of 0.4 and wear loss of 3.64mg in rubbing with GCr15 for 1km. Rolling of 4mm rolled plate with highest comprehensive property in different thickness reduction and roller temperature show that with deformation increasing, effects of temperature on strength became smaller, which counter to elongation. The highest tensile strength and elongation are 305MPa rolled 20% at 200℃ and 39% rolled 50% at 200℃ respectively. Moreover, multi-pass rolling of 4mm rolled plate is studied with 40% thickness reduction at 230℃ of roller. The results show that sheet after 4 passes has highest strength of 258MPa, and elongation of sheet after 3 passes became 42.3%. The lamellar turned into graininess partially when rolling. Keywords: ZnAl33 alloy；Rolling；Mechanical properties -II- 目 录 摘 要 ......................................................................................