【作者】 孙超；

【导师】 孙红镱；

【作者基本信息】 哈尔滨理工大学 ， 材料加工工程， 2016， 硕士

【摘要】 随着航空事业的高速发展,对飞机安全性的要求不断提高,轮毂作为飞机起飞和降落的主要受力部件,对其各项力学性能的要求也不断提高。由此,铝合金轮毂的密度小、热导率高、减震效果明显、成型性好的特点就尤为突出。本文以A109铝合金轮毂为研究对象,通过改变锻造工艺、热处理工艺,以及控制粗晶并提出更加高效、严谨的操作方法来整体提高其力学性能和成品率。将依据原工艺与新工艺所生产的轮毂在不同位置取样,将试样进行力学性能的测试,比较二者力学性能的优劣,结果表明,将铸锭3次镦粗、2次拔长后模压的新工艺对轮毂锻件的力学性能提升更大。此外,将锻件的锻造温度区间确定为400~460 oC,而开锻温度区间应定为440~460 oC,终锻温度保证在400 oC以上,可使模锻件的内部质量和性能得到显著提高。通过对试样选取不同时效温度、保温时间后,对其力学性能的数值进行比较分析,结果表明,试件时效温度为155 oC,保温时间为10 h时,轮毂模锻件的力学性能稳定。通过多组试件改变挤压温度、模具温度、模锻道次,来观察粗晶的长大情况,从而得出,挤压温度控制在410~440 oC,模具温度应控制在400~450 oC,模锻道次控制在2次左右,尽量不超过4次,可有效控制粗晶。在多次加工轮毂的过程中对各个工序进行改变和尝试,总结出能有效提高轮毂成品率的优化工艺流程:将铸锭定温470 oC,保温6 h以上,反挤压,在自由锻压力机上,模具定温450 oC,使用300 mm的锻钳,进行倒小棱后压至300 mm,在镗床上钻孔、镗孔,热处理后进行验收。更多还原

【Abstract】 With the high-speed development of aviation industry and for the requirement of increasing the aircraft safety, the requirement of mechanical properties of wheel hubs which are the important mechanical parts when a plane lands and takes off is increasing. Smaller density, higher heat conductivity, better damping effect and formability are its obvious advantages.In this paper, A109 aluminum alloy wheel hub was the research object. By changing its forging process, heat treatment process, controlling the coarse grain and putting out efficient and precise method of operation, its mechanical properties and yield are improved.Comparing the original process with the new process, and the results show that the new one that is three times in upsetting and twice pulling is improving the mechanical properties more. Otherwise, forging temperature is 400~460 oC, open forging temperature is 440~460 oC, and finish forging temperature is 400 oC.Through choosing different aging temperature and holding time and analyzing the data, the results show that when its aging temperature is 155 oC and holding time is 10 hours, its mechanical properties are steady.By changing extrusion temperature, mold temperature and times of forgings and observing the growing of coarse grain, the results show that when extrusion temperature is 410~440 oC, mold temperature is 400~450 oC, and the times is between 2 and 4, the coarse grain can be controlled.In the process of processing wheel hub, a high quality operation method can be concluded. It puts the ingot casting temperature 470 oC, heat preservation over 6 h, backward extrusion, in free forging presses, die fixed temperature 450 oC, uses 300 mm forging pliers to pour small edge to 300 mm, bores, drills, and accepts after heat treatment.更多还原