热压方程的研究——铁粉热压实验验证

来源期刊：中南大学学报(自然科学版)1985年第1期

论文作者：李旭 黄培云

文章页码：119 - 126

关键词：热压过程； 方程参数； 压制压力； 实验验证； 电解铁粉； 实验结果； 保温时间； 压制模； 弛豫时间； 雾化铁粉

摘    要：本文根据黄培云粉末压型理论,导出了能进行定量计算的热压方程: ln（d_m-d₀）d/（d_m-d）d₀=（（P/M₀））^1/m₀ e^-t/τ₂+（P/M）^1/m(1-e^-t/τ₂)式中:d是压块密度,d₀是粉末的初始密度,d_m是金属的理论密度,P是压制压力,m是非线性指数,m₀是初始非线性指数,τ₂是恒应力下的应变弛豫时间,M是压制模数,M₀是初始压制模数。用铁粉热压实验对所导出的方程进行了验证,结果表明,上述方程不但在本实验条件下与实验结果较好地符合,而且能预测本实验范围以外的结果。

Abstract: A quantitative equation which can be used to describe hot-pressing densification process, based on the time-dependent mathematical model for the compaction of powders proposed by Professor Huang Peiyun, has been derived. The equation has the form: ln （d_m-d₀）d/（d_m-d）d₀=（p/M₀）^1/m₀e^-t/τ₂=（P/M）^1/m（1-e（-t/τ₂）） where d is the specimen density, d_m, the theoretical density, do the initial density, P the applied external pressure, m the non-linear index, M the modulus of pressing, τ₂ the strain relaxation time at constant stress. The hot-pressing experiment was carried out with atomized iron powder in graphite die. The range of temperature was from 600 to 900℃, the pressures from 90 to 300kg/cm² and the time from 0 to 30 rain. Experimental results showed satisfactory agreement with the predications of the equation.