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Additive manufacturing (AM) of Inconel 718, IN718, is increasingly being used for the manufacture of complex geometry parts for high temperature applications. However, the low surface integrity and build resolution of as-built AM IN718 parts demands post processing such as machining. This paper reviews the machining of AM IN718 to understand the effect of anisotropic behaviour of the AM part and the hardening post AM treatment on the machinability of the latter. A better understanding on the cutting parameters and machining performance measures such as cutting forces, tool wear, chip morphology and surface integrity of workpiece led to the development of a workplan for future investigation.

Laser Sintering offers manufacturers freedom of design, which enables creating parts with complex geometries. However, very little investigation has been made into the effects of geometry on mechanical properties of the parts. In the present study, Laser Sintered Nylon 12 parts with different section thickness are subjected to displacement controlled tension-tension and force-controlled fully reversed fatigue loading to investigate the effect of geometry on their fatigue behavior. Section thickness of the parts is shown to have no significant influence on the fatigue behavior under tension only loading. However, fatigue life of parts under fully reversed loading is shown to increase with section thickness.

Laser sintering allows producing end-use parts directly from computer files with no tooling required. For these parts to be used in industrial applications, their mechanical properties throughout in-service applications must be examined. The aim of this article is to provide an understanding of the dynamic performance of laser-sintered Nylon 12 parts. To investigate the viscoelastic properties of the material, dynamic thermal mechanical analysis has been performed in different frequencies and temperatures. Tension–tension cyclic behavior of samples has been studied and creep is shown to have a great impact in such behavior in addition to fatigue. Stress relaxation plots are provided and compared with the cyclic loading plots validating the fact that samples experience a combination of creep and fatigue in tension–tension loading. Hysteresis loops indicate brittle crack propagation in the samples experiencing fatigue.

Potential uses of composite materials are currently being investigated by the automotive industry to reduce vehicle weight and CO2 emissions. Existing composite production processes are however, low volume and high cost. The aim of the present study was to develop a novel end-to-end production process to produce a light weight, cost effective polymer composite with reduced TAKT time and potential for structural applications. Components were produced from discontinuous random fibres mixed with an epoxy resin system. Static and dynamic mechanical testing as well as durability tests are in progress to evaluate the performance of these materials. Initial results were compared to Sheet Moulding Compound (SMC) as the benchmark composite material.\ud \ud