热磨法木片断裂力学模型及磨片参量的影响因素

Mechanical Model of Broken Chips and Influencing Factors of Grinding Parameter with Hot Mill method

将热磨机磨片把木片原料研磨为纤维的过程转化为木片断裂的形式,运用断裂力学理论对其研究。当磨片研磨木片时,木片的破坏简化为Ⅱ-Ⅲ复合型(滑开型+撕开型)裂纹的扩展问题,建立木片断裂过程的力平衡方程,研究木片断裂力学模型,分析纤维研磨过程中磨片施力方式与木片原料研磨之间的关系;运用含斜裂缝有限板裂缝尖端的应力强度因子计算公式,推导热磨法木片断裂的断裂判据,并对磨片参量影响的因素进行分析,为磨片的设计提供理论依据。

We studied chips fracture converted from the process that defibrator dissociated fiber from chips raw material by using fracture mechanics. Chips damage in the effect of defibrator was seen as（ Ⅱ-Ⅲ） the extended problem of mixed mode（ slide open type＋tear type） crack,by which the force balance equation was established in the process of the fracture of chips raw material to study chips fracture mechanics model,and express the relationship between abrasive disc forces and chips raw materials dissociating in the process of fiber grinding. Using calculation formula of stress intensity factor including diagonal crack and limited board crack tip,the fracture criterion chip broken by hot mill grinding was deduced,and correlation analysis for factors of grinding was got.