Hot granule medium pressure forming(HGMF) is a technology in which heat-resistant granules are used to replace liquids or gases in existing flexible-die forming technology as pressure-transfer medium. Considering the ...Hot granule medium pressure forming(HGMF) is a technology in which heat-resistant granules are used to replace liquids or gases in existing flexible-die forming technology as pressure-transfer medium. Considering the characteristic of granule medium that seals and loads easily, the technology provides a new method to realize the hot deep-drawing forming on high strength aluminum alloy sheet. Based on the pressure-transfer performance test of granule medium and the material performance test of AA7075-T6 sheet, plastic mechanics analysis is conducted for the areas, such as the flange area, force-transfer area and free deforming area, of cylindrical parts deep-drawn by HGMF technology, and the function relation of forming pressure is obtained under the condition of nonuniform distribution of internal pressure. The comparison between theoretical result and experimental data shows that larger deviation occurs in the middle and later period of forming process, and the maximum theoretical forming force is less than the experimental value by 24.6%. The variation tendency of the theoretical thickness curve is close to the practical situation, and the theoretical value basically agrees well with experimental value in the flange area and the top area of spherical cap which is in the free deforming area.展开更多
对半连续铸造获得的镁合金棒材通过大比率挤压细化组织,制备出各种厚度的薄板,再通过单向和交叉轧制获得平均晶粒尺寸<5μm的细晶镁合金薄板。所制备镁合金薄板经523 K×30 m in退火后发生静态再结晶,孪晶、位错、亚结构基本消失...对半连续铸造获得的镁合金棒材通过大比率挤压细化组织,制备出各种厚度的薄板,再通过单向和交叉轧制获得平均晶粒尺寸<5μm的细晶镁合金薄板。所制备镁合金薄板经523 K×30 m in退火后发生静态再结晶,孪晶、位错、亚结构基本消失,板材具有良好的力学性能和组织结构。交叉轧制改善了镁合金板材的各向异性,薄板具有良好的热拉深性能,成功地拉深出质量完好的筒形件,未显示出“凸耳”现象,极限拉深比达到2.60。展开更多
基金Projects(51305386,51305385)supported by the National Natural Science Foundation of ChinaProject(E2013203093)supported by the Natural Science Foundation of Hebei Province,China
文摘Hot granule medium pressure forming(HGMF) is a technology in which heat-resistant granules are used to replace liquids or gases in existing flexible-die forming technology as pressure-transfer medium. Considering the characteristic of granule medium that seals and loads easily, the technology provides a new method to realize the hot deep-drawing forming on high strength aluminum alloy sheet. Based on the pressure-transfer performance test of granule medium and the material performance test of AA7075-T6 sheet, plastic mechanics analysis is conducted for the areas, such as the flange area, force-transfer area and free deforming area, of cylindrical parts deep-drawn by HGMF technology, and the function relation of forming pressure is obtained under the condition of nonuniform distribution of internal pressure. The comparison between theoretical result and experimental data shows that larger deviation occurs in the middle and later period of forming process, and the maximum theoretical forming force is less than the experimental value by 24.6%. The variation tendency of the theoretical thickness curve is close to the practical situation, and the theoretical value basically agrees well with experimental value in the flange area and the top area of spherical cap which is in the free deforming area.
文摘对半连续铸造获得的镁合金棒材通过大比率挤压细化组织,制备出各种厚度的薄板,再通过单向和交叉轧制获得平均晶粒尺寸<5μm的细晶镁合金薄板。所制备镁合金薄板经523 K×30 m in退火后发生静态再结晶,孪晶、位错、亚结构基本消失,板材具有良好的力学性能和组织结构。交叉轧制改善了镁合金板材的各向异性,薄板具有良好的热拉深性能,成功地拉深出质量完好的筒形件,未显示出“凸耳”现象,极限拉深比达到2.60。
