Diode area melting single-layer parametric analysis of 316L stainless steel powder

Diode area melting (DAM) is a novel additive manufacturing process that utilises customised architectural arrays of low power laser diode emitters for high speed parallel processing of metallic powdered feedstock. The laser diodes operate at shorter laser wavelengths (808 nm) than conventional SLM fibre lasers (1064 nm) theoretically enabling more efficient energy absorption for specific materials. This investigation presents a parametric analysis of the DAM process, identifying the effect of powder characteristics, laser beam profile, laser power and scan speed on the porosity of a single-layer sample. Also presented is the effect of process energy density on melt pool depth (irradiated thermal energy penetration capable of achieving melting) on 316L stainless steel powder. An analysis of the density and the melt depth fraction of single layers is presented in order to identify the conditions that lead to the fabrication of fully dense DAM parts. Energy densities in excess of 86 J/mm3 were theorised as sufficient to enable processing of fully dense layers

Selective laser melting of magnesium and magnesium alloy powders: A review

10.3390/met7010002Metals71

Enhancing the ignition, hardness and compressive response of magnesium by reinforcing with hollow glass microballoons

10.3390/ma10090997Materials10999

Magnesium-?-tricalcium phosphate composites as a potential orthopedic implant: A mechanical/damping/immersion perspective

10.3390/met8050343Metals8534

Enhancing the hardness and compressive response of magnesium using complex composition alloy reinforcement

10.3390/met8040276Metals8427

Significantly enhancing the ignition/compression/damping response of monolithic magnesium by addition of Sm2O3 nanoparticles

10.3390/met7090357Metals7935

Structural, mechanical and thermal characteristics of Al-Cu-Li particle reinforced Al-matrix composites synthesized by microwave sintering and hot extrusion

In this study, Al-Cu-Li (5, 10 and 15 vol%) alloy particles reinforced Aluminum matrix composites were synthesized by powder metallurgy route incorporating microwave sintering and hot extrusion processes. The effects of novel Al based alloy reinforcement on the microstructure, mechanical and thermal characteristics of the Al/Al-Cu-Li composites were investigated. Uniformly distributed Al-Cu-Li alloy particles were observed in the microstructure of the composites. The synthesized materials were characterized for microhardness, co-efficient of thermal expansion, tensile and compressive properties. The results reveal that, hardness, Young's modulus, ultimate compression strength, ultimate tensile strength, yield strength and elongation of Al/15Al-Cu-Li composite improved by ?186%, 53%, 42%, 47%, 41%, and 48%, respectively in comparison to pure Al. This increase in strength and hardness values is attributed to the distribution of hard and brittle aluminum-based alloy phases in the ductile Al matrix. Furthermore, coefficient of thermal expansion of composites revealed the better thermal stability behavior for Al/15Al-Cu-Li composite compared to pure Al. The results of the present study suggest that the Al/15Al-Cu-Li composite is a very promising candidate for aerospace applications, which are extremely demanding in terms of both comprehensive mechanical properties and lightweight.This publication was made possible by NPRP Grant 7-159-2-076 from the Qatar National Research Fund (a member of the Qatar Foundation).Scopu

Enhancing compressive, tensile, thermal and damping response of pure Al using BN nanoparticles

In the present study, aluminum based metal matrix composites containing various amounts of boron nitride (BN) nanoparticulates (0, 0.5, 1.0 and 1.5 vol.%) were fabricated by using the powder metallurgy (PM) technique involving microwave sintering and hot extrusion process. The microstructure, physical, thermal, mechanical and damping characteristics of the extruded nanocomposites were investigated. Field emission scanning electron microscopy (FE-SEM) study shows the evenly distributed BN particles in Al matrix. Mechanical analysis indicates that the compression, hardness and tensile strength of Al-BN nanocomposites increases with increasing amount of BN content. Particularly, a significant improvement in the tensile strength (?36%) is achieved in Al-1.5 vol.% BN nanocomposite when compared to the pure aluminum (Al). This improvement strength can be attributed to the dispersion hardening of the Al matrix due to the presence of hard BN nanoparticles. Thermal analysis shows that the coefficient of thermal expansion (CTE) decreases with increasing amount of BN which may be ascribed to inherent low CTE of BN nanoparticles used as reinforcement. The addition of BN nanoparticulates enhanced the damping characteristics of pure Al with Al-1.5 vol.% BN nanocomposite exhibiting the maximum damping capacity and damping loss rate with a minimum change in elastic modulus. The improved combination of properties exhibited by Al-BN nanocomposites make them potential candidates for a wide spectrum of industries especially for weight critical applications.This publication was made possible by NPRP Grant 7-159-2-076 from the Qatar National Research Fund (a member of the Qatar Foundation)

A new method to lightweight magnesium using syntactic composite core

10.3390/app10144773Applied Sciences (Switzerland)1014477

A novel method of light weighting aluminium using magnesium syntactic composite core

10.3390/cryst10100917Crystals10101-1