Heat Treated Aluminium

Heat Treatment of aluminium products can be problematic, services that we offer in support of this: Cladding Diffusion within Aluminium alloys that are clad in pure aluminium needs to be tightly controlled in order to excessive diffusion of the cladding material into the base metal. Using our metallographic techniques, we are able to assess against national, international and prime specifications ensuring that your furnace controls meet relevant requirements.
Incipient Fusion/melting- occurs in precipitation-hardenable aluminium alloys which are typically heat treated in order to further enhance their properties, however, over heating during the heat treatment process can lead to incipient melting, where certain areas with a higher alloy content area such as a grain boundary can melt before the rest of the material resulting in degredation of the mechanical and corrosion properties. Once occurred, the process is irreversible, resulting in scrapping of the material
Eutectic Melting – The solution heat treatment temperature of some aluminium alloys and the eutectic/incipient melting temperature can be very close to each other. Too low a temperature will not fully solutionise the material, whilst too high a temperature can result in eutectic melting the material. Because of the very narrow temperature band, a small error in furnace calibration or control can result in overheating and therefore incipient/eutectic melting of the material.
High Temperature Oxidation - sometimes referred to as hydrogen blisters occur due to the reaction of water vapour with the surface of the aluminium and can occur during the solution heat treatment process in a furnace that has a relatively high moisture content. The reaction may lead to blisters below the surface of the material, affecting the appearance of the product. In general terms, the higher-strength alloys are far more susceptible that lower-strength alloys, with alclad alloys being practically immune to HTO blister formation.