摘要
研究结果表明:①型砂在静态压力作用下,有侧限情况下的应力-应变(σ-ε)关系曲线分为三个阶段,即退让阶段、紧实阶段和应变截止阶段。②膨润土含量主要影响σ-ε曲线的第二、三阶段,膨润土含量越大,型砂在紧实过程中吸收的应变能越大,从而得到的砂型强度也大。③紧实率对σ-ε关系的影响主要在退让阶段,紧实率愈大,退让阶段愈长。应力与紧实度(硬度与强度)之间具有对应关系。④型砂和砂箱内壁之间的摩擦系数为0.5,摩擦角约为27°。
Xie Bin and others. Study on Some Basic Mechanics Performances of Moulding Sand. The test results showed that: ①Under the static effects and the confining states, the stress-strain (σ-ε) relation curve of moulding sand can be divided into three stages, i. e.: deformation stage, compaction stage and strain stage. ②The content of bentonite mainly affects the second and third stage. The greater the bentonite content, the greater the strain energy absorbed during the compact process of moulding sand and it results in greater sand mould strength. ③The effects of compactibility vis-a-vis with σ-ε relation are mainly in the deformation stage. Stress and compactibility (hardness and strength) possess a corresponding relationship. ④The friction coefficient arisen between the moulding sand and the inner walls of the flask is 0.5 and the angle of friction is 27°。
基金
国家自然科学基金
