一、前言为了在理论上阐明造型时型砂的紧实状态或紧实过程,进行力学分析是必要的。虽然对型砂进行这样的研究非常少,但是在其它粉状物料的加工领域中,关于粉体的输送、贮藏,成型等已进行了很多的研究,并且其基本的力学特性也已经相当清楚。其中与粉体流动或紧实关系最密切的是剪切特性,此外内摩擦角、壁面摩擦角等特性值也是决定粉体的流动或紧实时的应 I. Preface In order to clarify the compact state or compaction process of molding sand in theory, it is necessary to carry out mechanical analysis. Although there has been very little research on molding sand, much research has been done on the transportation, storage, molding and the like of the powder in the field of processing of other pulverized materials, and the basic mechanical properties thereof have also been fairly clear. Which is closely related with the flow of powder or compact shear properties, in addition to the internal friction angle, wall friction angle and other characteristics of the value is also determined when the powder flow or tight should