高强度钢储能螺母凸焊工艺非线性多元回归设计

通过正交试验法,研究了22MnB5高强度钢与M8法兰焊接螺母电容储能焊工艺,以凸焊接头螺母顶出力f为衡量接头质量的主要考察指标,以电极压力x1、焊接电压x2、电容容量x3等三个主要焊接参数以及各参数间的交互作用作为相互独立的考察因素,建立了一种描述工艺参数与接头质量之间关系的三元三次非线性回归模型,通过遗传算法对模型进行了优化求解,并通过试验对模型进行了检验。结果表明,回归模型值与试验值的误差均在10%以内,模型具有较高的精度。     

Numerical modeling and simulation of metal powder compaction of balancer

1 Introduction “Cold” compaction, which is operated at room temperature, is currently the most generally used compacting method in powder metallurgy industry. Under this circumstance, metal powder is often considered a kind of time-independent, elasto-…     

Numerical simulation for sheet metal forming process of 16Mn blade of large concrete-mixer truck

A finite element analysis method was used to simulate the stamping process of the blade of a large concrete-mixer truck. The updated Lagrange method and the elasto-plastic constitutive equation were adopted to solve the large strain and displacement deformation of the blade. A modified Coulomb friction model was used to solve the sliding contact between the blade and the dies. The yon Mises stress distribution in the blade, the spatial displacement variation and the spring-back of the typical node were investigated in the simulation. The yon Mises stress in the blade where the spring-back occurs is lowered from 463.0 MPa to 150.0 MPa before and after the spring-back.A typical node in the blade has a 3.33 mm spring-back in Z direction. The results of the experiments agree well with the simulation. The analysis results are valuable for designing optimal tool dies.     

仫佬族春节和做依饭

仫佬族居住在广西北部山区一带,这里景色优美,风光宜人,素有"小桂林"之称。仫佬族同胞主要从事种植业与采集业。仫佬族节日很多,也很独特,其最为隆重的首推春节与做"依饭节"。买新水仫佬族有着自己独特的春节与传统的习俗活动——这便是"买新水"。它源于仫佬族对祖先的祭祀。古时,仫佬族人在父母去世时,孝子要到池边或河边痛哭一番,并散纸     

仫佬族春节和做依饭

仫佬族居住在广西北部山区一带，这里景色优美，风光宜人，素有“小桂林”之称。仫佬族同胞主要从事种植业与采集业。仫佬族节日很多，也很独特，其最为隆重的首推春节与做“依饭节”。买新水仫佬族有着自己独特的春节与传统的习俗活动——这便是“买新水”。它源于仫佬族对祖先的祭祀。古时，仫佬族人在父母去世时，孝子要到池边或河边痛哭一番，