Methoding and Simulation of LM 6 Sand Casting for Defect Minimization with its Experimental Validation

Abstract

The solidification of metals continues to be a phenomenon of great interest to physicists, metallurgists, casting engineers and software developers. It directly affects the production cycle time, internal quality of castings and material utilization (yield). The process of casting solidification is complex in nature and the simulation of such process is required in industry before it is actually undertaken. The volumetric contraction accompanying solidification of molten metal manifests in defects like shrinkage cavity, porosity, and sink. These defects can be minimized by an intelligent methoding and simulation using casting software. In this paper, an attempt has been made to redesign and develop a casting free from defects, in particular, shrinkage defect. The component taken for methoding and simulation study was subjected to high amount of shrinkage defects which was the major cause for the rejection in the foundry. It also was having very low yield as 45 % as per the foundry information. The component under study consists of square shaped (at top) plate having three perforations with diminishing height (at bottom) and subjected to multiple hot spot. Therefore, optimum location of feeder has been identified by carrying out various simulation trials. Proper feeding aids have helped in getting the hot spot completely shifted inside the feeder. Simulation based approach has helped in the improvement of the feedability index which represents yield of feeders and quality of casting (percentage of volume free from shrinkage porosity). The simulations results were compared with the experimental trial and the comparison was found to be in good agreement.

Classification of Metals used in the Sand Casting Process

“…C. M. Choudhari (2014) have used LM6 for this simulation because it is suitable for sand casting. It is corrosion resistant and has greater strength and highly ductile in nature.…”

“…C. M. Choudhari (2014) simulated and compared the results of the LM 6 aluminium alloy by using AutoCAST-X software. This material has been used for casting material.…”

A Review on Casting Defects Analysis for Optimization of Process Parameters to Minimize Casting Defects

“…This study showed that simulation can be effective for identification of location for occurrence of casting defect as it does not involve any wastage of material or labour. The simulation results were compared with experimental results and it was found that the analysis optimized the design of feeder by improvement in yield by 20% [13]. K M Maneesh et al have described a way to minimize the health hazards in industry to make the work condition more effective and to improve poor quality and productivity of industry by minimizing casting defects.…”

Simulation tools in enhancing metal casting productivity and quality: A review

“…Efforts have been made in the past to obtain high-quality defect-free castings by developing an in-depth understanding of the areas such as (a) design of runner and gating systems, 32–40 (b) design of feeding systems (locations and number of risers), 41–45 (c) filling and solidification during different casting processes, 46–50 (d) casting process parameters (thermo-physical data, injection parameters, etc. ), 50–54 (e) stress distribution in cast products, 55–59 and (f) quality control and assurance of the cast products.…”

“…In one study, Choudhari et al 43 demonstrated the shrinkage defect elimination in stepped plate casting using AutoCAST-X software followed by experimental validation. This software uses gradient vector method to calculate the temperature gradients (feed metal paths) inside the casting.…”