摘要
采用多层喷射沉积技术制备６０６６铝合金（Ａｌ１．３７Ｓｉ１．３７Ｍｎ０．７７Ｃｕ）锭坯，研究了后续半固态挤压工艺的可行性，及其对材料组织与性能的影响。结果表明，多层喷射沉积６０６６铝合金的平均晶粒度约为１５μｍ，呈等轴晶；在固相线以下退火４０ｍｉｎ后，组织无明显粗化，在半固态发生的晶粒长大符合Ｏｓｔｗａｌｄ晶粒粗化动力学方程，半固态典型组织为球形或近球形的固体颗粒分布于液相中，为适宜于半固态加工的搅溶组织。半固态挤压成形力约为传统热挤压的１／３，挤压件具有良好的第二相粒子分布状态，在Ｔ６热处理过程中组织发生再结晶，晶粒明显细化，二相粒子平均粒度由热挤压态的１μｍ增至２μｍ，体积分数有所增加，材料力学性能达到传统热挤压件水平。
6066 aluminum alloy billets(Al1.37Si1.37Mg0.77Cu) were produced by multilayer spray deposition technology, studies were carried out to evaluate the feasibility of subsequent semisolid extrusion and its influence on microstructure and mechanical properties. Assprayed grain was equiaxed with mean size of about 15 μm, grains coarsened slightly in full solid state, which are in good agreement with Ostwald coarsing mechanism. Typical microstructures of assprayed materials heated to semisolid state are of spheriodical solid particles distributed in liquid phase, which are thixotropic microstructure fit to thixoforming. The necessary extrusion force in semisolid state is about 1/3 of that in coventional hot extrusion. Asextruded materials have uniform precipitates distribution and achieve finer recrystallization grains under T6 condition. Mean precipitated size increase from 1 μm to 2 μm after T6 treatment, and mechanical properties reach that of conventional hot extruded materials.
出处
《中国有色金属学报》
EI
CAS
CSCD
北大核心
1998年第2期191-196,共6页
The Chinese Journal of Nonferrous Metals
关键词
喷射沉积
半固态
铝合金
半固态挤压
铸造
spray deposition semisolid aluminum alloy nearnetshaping microstructure
