Jianzhong WANG
金属学报(英文版)
doi:10.1016/S1006-7191(08)60122-2
A new method for producing higher density PM parts, high velocity compaction (HVC), was presented in the paper. Using water atomized pure iron powder without lubricant admixed as the staring material, ring samples were compacted by the technique. Scanning electron microscopy (SEM) and a computer controlled universal testing machine were used to investigate the morphologies and the mechanical properties of samples, respectively. The relationships among the impact velocity, the green density, the sintered density, the bending strength and the tensile strength were discussed. The results show that with increasing impact velocity, the green density and the bending strength increase gradually, so the sintered density does. In addition, the tensile strength of sintered material is improved continuously with the sintered density enhancing. In the study, the sintered density of 7.545~g/cm3 and the tensile strength of 190~MPa are achieved at the optimal impact velocity of 9.8 m/s.
关键词:
Powder metallurgy
,
high velocity compaction
,
green properties
,
stress wave
,
bending strength
王建忠曲选辉尹海清周晟宇
材料研究学报
采用高速压制技术制备铁基制品, 探讨了冲击能量及冲击速度与冲击行程之间的关系, 并研究了冲击能量、压制方式对生坯密度、最大冲击力、脱模力和径向弹性后效的影响. 结果表明: 在高速压制过程中, 冲击能量与冲击行程呈线性关系,而冲击速度与冲击行程呈抛物线关系. 生坯密度随着冲击能量的增加而逐渐增大.单次压制时, 当冲击能量增加到 6510 J时, 生坯密度达到7.336 g/cm3,其相对密度约为97%. 在总冲击能量相同的情况下, 两次压制制备出的试样生坯密度最大,三次压制的最小. 在高速压制过程中, 试样的脱模力及其径向弹性后效均远低于传统压制.
关键词:
材料合成与加工工艺
,
PM
,
green density
,
high velocity compaction
,
impact energy
,
withdraw force
闫志巧陈峰蔡一湘崔亮
金属学报
doi:10.3724/SP.J.1037.2009.00383
以Ti粉为原料, 高速压制内、外径分别为30和60 mm的圆环状及直径为20 mm的圆柱状两种试样, 探讨冲击能量、装粉量等对压坯密度的影响, 并寻求高速压制过程的合适表征方式. 结果表明: 对于内、外径分别为30和60 mm的圆环试样, 当冲击能量为3.804 kJ时, 可成形的压坯密度最大, 为4.00 g/cm3, 致密度为88.9%; 对于直径为20 mm的圆柱试样, 当冲击能量为1.217 kJ时, 可成形的压坯密度最大, 为4.38 g/cm3,致密度为97.4%. 对于同种试样, 压坯密度随冲击能量的增加而增大, 随装粉量的增加而减小. 质量能量密度能全面地表征试样大小、冲击能量和装粉量等不同参数下的压坯密度.
关键词:
Ti粉
,
high velocity compaction
,
green density
,
impact energy
,
impact energy per weight
