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对ZA27蜗轮毛坯进行半固态成形试验,在不同比压和模具温度条件下,对制件的宏观成形性和微观组织形貌进行了分析研究。结果发现:比压较小时,齿型无法成形,当比压为40～60MPa时,蜗轮成形性良好;当压力过高时,易形成纵向飞刺且脱模困难。随着压力的上升,制件微观组织发生明显的变化,球状及玫瑰状的半固态组织逐步发生断裂、变形及以龟斑状形貌排列的现象。当模具温度较低时,半固态浆料在模具中充型困难;当模温在200℃时,成形良好;在不同模温下,蜗轮齿顶的微观组织形貌差异较大,从玫瑰状转变为碎片状微观组织。
ZA27 worm gear blank semi-solid forming test, under different pressure and mold temperature conditions, the macroscopic formability of the workpiece and the microstructure morphology were analyzed. The results show that when the specific pressure is small, the tooth shape can not be formed. When the specific pressure is 40 ~ 60MPa, the worm wheel formability is good. When the pressure is too high, it is easy to form longitudinal fliter and the demoulding is difficult. With the increase of pressure, the microstructure of the workpiece changes obviously. The phenomenon of spherical and rose-like semi-solid structure gradually ruptures, deforms and arranges in the form of turtle spots. When the mold temperature is low, the semi-solid slurry filling in the mold is difficult; when the mold temperature is 200 ℃, the forming is good; under different mold temperatures, the top of the worm gear has a great difference in microstructure, Transformed into fragmented microstructure.