模具铜合金材料组织与强韧性研究

【作者】 李海兰；

【导师】 王智平； 路阳；

【作者基本信息】 兰州理工大学 ， 材料加工工程， 2004， 硕士

【摘要】 近年来，板式换热器行业引用了一种进口高铝青铜模具材料代替传统的铁基模具钢，该材料制作的模具具有强度高，摩擦系数小，耐磨性好等优点，是拉伸不锈钢这类变形阻力大的优秀模具材料，为实现这种模具材料的国产化，降低模具成本具有重要意义，借鉴进口高铝青铜模具材料的成分配比，采用普通熔炼炉进行熔炼。本文将对其铸态组织、热处理组织与性能之间的关系进行研究，确定其满足模具使用性能的组织。 采用光学显微镜、扫描电镜、X射线衍射分析和力学性能测试等方法研究了铸态和固溶时效对高铝青铜（13-15％）组织与性能的影响。试验结果表明：该高铝青铜随固溶温度升高，晶粒长大，k相和γ₂相大量溶解；随时效温度的升高，强化相由部分析出到完全析出，甚至发生共析反应，导致力学性能降低。高铝青铜进行950℃×2h固溶和500℃×5h时效可获得高强韧性β相中均匀分布k相和γ₂相的组织，因此该材料在该固溶时效条件下具有较高的综合力学性能。更多还原

【Abstract】 In recent years, a new type of high - aluminium bronze die had been imported to replace some iron-based dies, such as 35CrMo et. In heat-exchanger production, the new aluminium bronze die material processes some super properties, such as high strength, low friction coefficient and wear-resistance. It belongs to excellent die material in the field of drawing stainless steel. In order to realize localization of manufacture of high-aluminium bronze die material and decrease cost of copper alloy die material, the ordinary smelting process was used by referring to composition of imported high-aluminium bronze. In this paper, microstructure and propertied were studied so that the best microstructure of die material can be obtained.Effect of solid solution and aging treatment on microstructure and properties of multi-aluminum bronze is studied by using optical microscope, SEM, XRD and mechanical property testing. The results show that the high-aluminum grain size increases and r2 phase K phase have been soluted with the increase of solution treatment temperature, and the thermal brittle at high solution temperature results from the segregation of inclusions at grain boundary; with increase of aging temperature, the strength phases precipitate from partly to wholly and B phase will transform into r2+a eutectoid which leads to mechanical properties decreasing . distributing of K phase and r2 phase in high-strength B’ phase of high-aluminum bronze can be obtained by 950C X 2h oil-quenching and 500CX5h aging treatment. So comprehensive mechanical properties of the high-aluminum bronze are higher under such heat treatment technique.更多还原