A study of porosity formation in pressure die casting using the Taguchi approach

Abstract

Porosity is one of the defects most frequently encountered in aluminium die castings. Porosity formation causes costly scrap loss and limits the use of die-cast parts in critical high-strength applications. The amount of porosity is closely related to die casting process parameters. A considerable reduction in porosity formation can be obtained using the Taguchi approach in the die casting process. An example of the off-line technique used in the Greek die casting industry is given, with the aim of illustrating practicality and ease of use by industry engineers and managers. In the thick-walled sample casting studied, the final intensification pressure contributed 69 per cent towards the reduction in porosity. Among the other parameters considered, melt and die temperatures have a smaller effect (about 10 per cent), followed by the plunger velocities in the second and first stages which have only a slight effect on porosity formation. In addition, the expected quality improvement and the cost savings under optimum parameter settings were evaluated. The expected improvement in reduction in porosity formation was found to be 48.6 per cent, while the expected cost savings for multiple casting parts under optimum conditions was calculated to be 71.4 per cent/$1 loss before the experiment.

Effect of Casting Thickness and Plunger Velocity on Porosity in Al Plate Diecasting

“…먼저 슬리브에 용탕을 주입하고, 슬리브 내의 공기혼입을 최소화하기 위해 플런저를 느리게 이동하여 용탕이 게이트 부분까지 충전하여 슬리브 내의 용탕을 완전히 충전시킨다. 그 후 플런저를 빠 르게 이동시켜 캐비티를 완전히 충전시킨다 [5,[8][9][10][11]. 일반적으 로 용탕을 캐비티 내에서 사전 충전하지 않고 게이트까지 충 전 후 플런저가 고속으로 이동하나, 북미의 경우 공기혼입을 최소화하기 위해 플런저가 고속으로 이동하기전에 전략적으로 캐비티 내 35%정도를 사전 충전하기도 한다.…”

Multi-Response Optimization of Die Casting Process for Lock Assembly of a Two Wheeler

“…Process parameters like plunger velocity and die temperature were optimized by Tsoukalas et al, [2] using Taguchi method to improve quality and to reduce the cost. Guharaja et al, [3] accomplished optimal settings of various significant process parameters like green strength, moisture content, permeability, and mould hardness for minimizing green sand casting defects using Taguchi's parameter design approach.…”

Modeling and Optimization of Die Casting Process for ZAMAK Alloy

“…Similarly, process parameter like plunger velocity and die temperature were optimized to improve quality and to reduce cost using Taguchi method by Tsoukalas et al [7], Guharaja et al [8], accomplished optimal settings of various significant process parameters such as green strength, moisture content, permeability and mold hardness for minimizing green sand casting defects using Taguchi's parameter design approach. Anastasiou [9] investigated the effects of process parameters on porosity formation in the pressure die casting process to improve casting quality using Taguchi method.…”