Microstructural evolution and mechanical properties of LM6 Al alloy

In this paper, multi-axial compression of LM6 Al alloy were performed at room temperature using strain of 0.2 in each pass. Total cumulative strains 0.6, 1.2 and 1.8, were applied in three, six and nine passes, respectively. Microstructural evolution is studied using light optical microscopy of the compressed specimen. Properties (tensile strength, hardness, toughness) of deformed specimens were studied using tensile and hardness tests, and relate them with their microstructures and fractographs. As passes increased from zero to nine, 62% of tensile strength of the material is increased along with hardness from 52 VHN to 74VHN.

Fractographical Analysis of Screws Used for Truck Cab Holding

The research deals with determination of the breaking cause of the screws used to attach the truck cabins. Scanning electron and light optical microscopy were used for engineering investigation of the fracture cause. Fractographical and structural analysis revealed fatigue mechanism of the screw fracture with morphology corresponding to the combination of tensile and bending stresses. Based on the acquired results a structural adjustment was recommended to the customer.

Characterisation of Steel Composites Produced by the Damascus Technique

The Damascus technique is a manufacturing process where steels with different compositions, in particular the carbon content, are forge welded. Materials with contrary properties are generated by different carbon additions: e.g., substantial toughness and elongation are combined with high tensile strength and hardness. Since the 3rd century AD blades and weapons have been produced by this technique in Europe.In this work various Damascus steels with different compositions were investigated by means of metallographic methods. The focus is set on the interface between individual steel layers. While the majority of interfaces look uniform and are influenced only by carbon diffusion, some areas show the enclosement of oxides and slag stringers as a result of faulty workmanship during the forge welding process.After metallographic preparation the various microstructures were characterised by light optical microscopy and confirmed by Vicker´s microhardness measurements.