• CN:11-2187/TH
  • ISSN:0577-6686

›› 1990, Vol. 26 ›› Issue (3): 87-93.

• 论文 • 上一篇    下一篇

铸造砂型常温力学模型的系统辨识研究

罗爱华;王文清;戴绪绮;苏国勋   

  1. 华中理工大学
  • 发布日期:1990-05-01

THE SYSTEM IDENTIFICATION OF MECHANICAL MODELS OF SAND MOLDS AT ROOM TEMPERATURE

Luo Aihua;Wang Wenqing;Dai Xuqi;Su Guoxun   

  1. Huazhong university of Science and Technology
  • Published:1990-05-01

摘要: 本文用系统辨识的方法建立了铸造砂型的三类常温力学模型;内聚模型、附着模型和复合模型。模型精度在0.2以内。辨识结果表明:水玻璃砂型为内聚模型,提高其力学性能的根本途径在于对粘结剂的改性处理;粘土砂型为复合模型,提高其力学性能的根本途径在于附加其他粘结剂;树脂砂型为附着模型,提高其力学性能的根本途径在于提高树脂与砂粒之间的附着强度,有机硅烧能改善其附着强度,使砂型由附着模型转变为复合模型和内聚模型,力学性能得到大幅度提高。

关键词: 力学模型, 砂型, 系统辨识, TIG焊,表面示踪,光学反射原理,熔池流动行为

Abstract: By means of system identification, three types of mechanical models of sand molds at room temperature were developed in this paper:(1)cohesive model σ=K0+K1b; (2)adhesive model σ=K”0+K”1b+K”2b,(K =K”1/K”2<10); (3)mixed model σ=K”0+K”1b+K”2b,( K =K”1/K” ≥10).The precision of the models was within 0.2.The conclusions of system identification of models are as follows: (1) Silica bonded sand molds can be expressed as cohesive models, and the most effective method to improve the mechanical properties of them is the modification of the binders. (2) Clay-bonded sand molds can be expressed as mixed models, and the most effective method to improve the mechanical properties of them is in conjunction with other binders. (3) Resin-bonded sand molds can be expressed as adhesive models, and the most effective method to improve the mechanical properties of them is to increase the adhesive force between resin and sand grain .In addition, the addition of silage increased the adhesive force between sand grain and resin ,changed the models of sand molds from adhesive ones to cohesive and mixed ones ,and as a result, the mechanical properties of molds were greatly improved.

Key words: 力学模型, 砂型, 系统辨识, TIG welding, Atomic tracer method, Optical reflection principle, weld pool flow behavior