On optimal extrusion dies for rigid-plastic materials

Materials on Dies for Pressure Die Casting

In the contribution the stress of die materials of thermal fatigue is defi ned and material life is derived theoretically and compared with the measured values. The important properties of the die materials as thermal conductivity, coeffi cient of thermal expansivity, modulus of elasticity and mechanical properties are described. Binding to it single die materials as carbon steels and chrome-tu...

Plane Strain Slip Line Theory for Anisotropic Rigid/plastic Materials

A SLIP line theory governing states of incipient plane flow at the yield point load is developed for anisotropic rigid/plastic materials which exhibit a reduced yield criterion, governing states of plane flow, that depends only on the deviatoric parts of the in-plane stress tensor. It is shown that every homogeneous, incompressible material which complies with the principle of maximum plastic w...

Optimal Performance of Plastic Extrusion Process Using Fuzzy Goal Programming

Abstract—This study optimized the performance of plastic extrusion process of drip irrigation pipes using fuzzy goal programming. Two main responses were of main interest; roll thickness and hardness. Four main process factors were studied. The L18 array was then used for experimental design. The individualmoving range control charts were used to assess the stability of the process, while the p...

The Phenomenon of Durability Variable Dies for Aluminum Extrusion Profiles

Extrusion dies are usually regenerated several times (min 4 times). The phenomenon of extended life after each regenerative nitriding process has not been explained. In this work, the regeneration process of dies used in the extrusion of aluminium profiles has been presented. In the article, it was sought to explain the cause of increased die durability after the third or fourth nitriding. Also...

High-Tech extrusion with barrier-mixing screws and spiral mandrel extrusion dies