Comparative Study on Morphological, Physical and Mechanical Characteristics of L-PBF Based AlSi10Mg Parts with Conventional Stir Casted Al-10 %SiC Composites

M Saravana Kumar,S Robinson,E Mohan,D Thivya Prasad

doi:10.1007/s12633-021-01065-9

Abstract

Stir casting plays a major role in the production of Al-SiC10 % composites for aero space and automobile applications. However, obtaining the composites with homogenous distribution of the SiC particles, low porosity and without clustering of reinforcement particles are still a major problem faced by the research community. These kind of casting defects were overcome by the Additive Manufacturing (AM) technology. In this research, AlSi10Mg parts were manufactured by Laser-Powder Bed Fusion (LPBF) method, one of the AM techniques. The mechanical and morphological characteristics of Additive manufactured (AM) samples were compared with the Stir Casted (SC) samples. Both AM and SC samples were analyzed for the porosity% using the Optical Microscope (OM). From the porosity analysis, it was evident that the AM samples shows 14 % reduction in porosity when compared with the SC samples. Mechanical testing such as tensile test, hardness test, fracture toughness test and double shear stress were carried out. The results obtained from the tensile test reveals that the AM samples shows 28.6 % higher tensile strength than the SC samples. Similarly, the hardness test for the AM samples shows 23.69 % higher hardness strength than the SC samples. The fracture toughness test for the AM samples shows 50 % higher fracture toughness strength than the SC samples and from the results of double shear stress test proves that the AM samples shows 32.55 % higher shear stress than the SC samples. The outcome of this research proved that additive manufactured AlSi10Mg sample shows enhanced mechanical and morphological properties when compared with the conventional stir casting process.

Highlights

In the recent years, Additive Manufacturing (AM) plays a major role in high end applications such as biomedical, automobile and aerospace [1]
The results obtained from the tensile test AM samples show 14.6% higher tensile strength than the Stir Casted (SC) samples, from the hardness test AM samples show 18.6% higher hardness strength than the SC samples, from the fracture toughness test AM samples show 33.4% higher fracture toughness strength than the SC samples and from the double shear stress test prove that the AM samples show 24.6% higher shear stress than the SC samples
This was mainly due to the sintering effect caused by the laser which leads to the fusion of the particles which eventually makes the surface rougher when compared with the SC samples

Summary

Introduction

AM plays a major role in high end applications such as biomedical, automobile and aerospace [1]. In the AM process, the materials were built up by the sintering of particles layer by layer [2]. It can build complex object with high geometry and it can manufacture a component which was impossible in conventional manufacturing methods [3]. In the aerospace applications, AM is playing a significant role in weight reduction and increasing performance which in turn reduces cost of space missions [4]. Based on increased mechanical performance, aluminium alloys are used in the space industries due to their high strength to weight ratio and low cost [5]. The AlSi10mg was the commonly used alloy in the AM process, the manufacturability through AM was more challenging when compared with the stainless steels and the titanium alloys [6]

Methods

Results

Conclusion