【作者】 石磊； 田学雷；

【机构】 山东大学材料科学与工程；

【摘要】 热裂是铸造合金中常见的严重铸造缺陷,甚至是影响合金铸造性能的决定性因素。多年的深入研究形成和发展了多种热裂机理和计算模型。然而,热裂的形成机理和控制机制尚未弄清,许多试验结果对合金性能或加工工艺在热裂中的作用机理分析不相一致。本综述全面阐述了合金特别是铸造铝合金的热裂机理、热裂影响因素,从实验测试、理论评定两方面介绍了热裂倾向性评价方法,并详细总结了近年来两类分别基于观察性和力学性能的实验测试方法。测试收缩应力和线性位移的最新热裂测试方法将在本文中得以介绍。本文可为以后建立稳定可靠的热裂评价标准作出了有力的参考。更多还原

【Abstract】 Hot tearing is a common and severe defect in casting and it is perhaps the crucial issue defining an alloy’s castability.The subject has been deeply studied for decades,which has developed various theories and formed some computational models.However,the related formation mechanism and control of hot tearing are not clear.Experiments show inconsistent results and opinions about the effects of alloys or processing factors influencing hot tearing.This review roundly stated the mechanism and variables of hot tearing and introduced methods of assessing hot tearing susceptibility of especially aluminum casting alloys in terms of experimental and theoretical ways. Besides,this paper summarized experimental tests in detail,which are classified into two categories:tests by observation of hot tears;tests using mechanical techniques. Several new systems which measure contraction force and/or linear displacement have been developed and some are described in this paper.This review is aimed to provide strong reference for establishing stable and reliable hot tearing criterions in the future.更多还原