Synthesis and characterisation of hot extruded aluminium-based MMC developed by powder metallurgy route

Sambit Kumar Mohapatra,Kalipada Maity

doi:10.1186/s40712-016-0068-9

Abstract

BackgroundImprovement of the mechanical and tribological properties due to extrusion can be attributed to the improved density and excellent bond strength due to high compressive stress.MethodsTo avoid the product defects mathematically contoured cosine profiled die was used for the thermomechanical treatment. Improvement of mechanical characterization like density, hardness, compression test and three-point-bend test was inquired. Two body dry sliding wear behaviour of the prepared AMCs before and after extrusion were investigated by using a pin-on-disc wear testing method by varying the variable parameters like load (N), track diameter (mm) and RPM of the counter disc.ResultsThe effect of hot extrusion on mechanical and tribological characteristics of aluminium matrix composites (AMCs) developed by powder metallurgy route followed by double axial cold compaction and controlled atmospheric sintering was studied.ConclusionShearing of the fine distributed graphite particles at the tribosurface acts as a solid lubricant and decreases wear rate. At higher loading and sliding velocity condition a mixed type of wear mechanism was observed.

Highlights

Improvement of the mechanical and tribological properties due to extrusion can be attributed to the improved density and excellent bond strength due to high compressive stress
Over the last few decades, there has been considerable attention to the evolution of Al-based MMCs developed by powder metallurgy (P/M) route of manufacturing
The main advantage of this kind of manufacturing process is the good distribution of reinforcing particles, low processing temperature and the ability to produce near net shape products with intricate designs (Min et al 2005; Torralba et al 2003)

Summary

Introduction

Improvement of the mechanical and tribological properties due to extrusion can be attributed to the improved density and excellent bond strength due to high compressive stress. Aluminium metal matrix composites are the most versatile replacement of other alloys in the sector of automotive, aerospace, defence and sports because of its high strength to weight ratio, ease and prevalence of processing techniques, excellent thermal and electrical conductivity and the ability to sustain in uncertain thermal and mechanical loading environment. This emerging area has influenced the researchers to tailor the mechanical, thermal and tribological properties of the composite using different types of reinforcements with various percentages with types of manufacturing process (Yigezu et al 2013).

Methods

Results

Conclusion