摘要
研究改性对石膏硬化体热膨胀收缩特性的影响表明,随着改性剂的加入,可以显著减小或消除石膏在350～400℃区间,即ⅢCaSO_4→ⅡCaSO_4阶段的急剧收缩,而使其尺寸稳定性明显提高,石膏改性的机制可归结为改性剂改变了石膏在不同温度下的同质异构转变过程,从而抑制或减少随相变而产生的体积变化。
The effect of modification on the thermal expansion and contraction character of hardened gypsum body has been investigated. It was shown that the obvious shrinkage of gypsum on heating within the range 350~400C,i,e.at the stage of III CaSO4 II CaSO4 was reduced greatly by the addition of modifier,Thus, the dimensional stability of piaster mould was improved.The mechanism of modification couH b' consi lered as that th?- allotro-pic transformations of gypsum at different tempera!: ires were changed adding the modifier.by adding the modifier.
出处
《特种铸造及有色合金》
CAS
CSCD
北大核心
1990年第1期13-16,共4页
Special Casting & Nonferrous Alloys
