【摘要】 采用熔铸原位合成法制备Al-Ni/7050复合材料,结果显示,原位生成的Al-Ni相尺寸不一,以长径50μm以上为主,拉伸试验发现,Al-Ni硬脆相粗大是引起脆性断裂的主要原因。对7050-10Ni复合材料进行多道次热/冷轧制显示,Al-Ni相尺度与形态递进变化,采用矩形近似测量法测量和表征材料中大块板条第二相尺寸的变化规律,结果表明:轧制后,Al-Ni增强相破碎,由初始树枝状板条破碎为近等轴颗粒,其中冷轧后颗粒棱角破碎迹象明显,热轧后颗粒倾向于保持原有棱角,仅缩小颗粒尺寸,硬度测试表示,Al-Ni相尺寸与硬度有峰值对应关系,其中冷轧加工硬化趋势较明显。更多还原

【Abstract】 The Al-Ni/7050 composites containing two different mass fractions 5% and 10% of Ni have been fabricated by in melt reaction method,microscopic structure indicates that in situ forming Al-Ni phases vary in sizes,which are mainly above 50 μm.Fracture analysis shows that large Al-Ni brittle phase is the major reason of fracture failure.Microscopic structure of composites after multi-step hot/cold rolling showed that Al-Ni phase structure changed progressively,a new measurement method of the second-phase particle was introduced to characterize the change law of the reinforcing Al-Ni phase,the measurement result showed that,reinforcing Al-Ni particle was smashed,transformed from original long slab to nearly isometric grains,but during the hot/cold rolling process,Al-Ni phase size changed differently,and cold-rolling is more effective in smashing the Al-Ni phase than hot-rolling,hot rolling is inclined to maintain the edges of Al-Ni phase,hardness measurement indicated that corresponding relationship can be found between the hardness peak value and Al-Ni phase size,and hardening trend was obvious in Al-Ni/7050 composites after cold rolling process.更多还原