Baking Hardenability
Baking hardenability is the measure of the ability of a material to be hardened through a thermal cycle. It is a measure of how resilient a material is to extreme temperatures. This process of tempering steel takes place in a furnace when the heat hardens the steel enough to create the desired strength. Baking hardenability is an important measured parameter when manufacturing components, as the performance of the component in a working environment can be greatly affected by the hardenability of the material.
Baking hardenability is measured by heating a specimen of the material up to a certain temperature. The specimen is then monitored for time and temperature, to determine the rate of cooling needed to reach a desired degree of hardness. The specimen is then cooled down rapidly and then re-heated until the desired hardness is attained. The hardness attained is then determined and compared to the desired amount.
The factors that affect baking hardenability are the rate of cooling, temperature and cooling time, chemical composition, and grain size. The chemical composition of the material, specifically carbon and alloying elements, will determine the degree of hardenability. The grain size of the material affects the way that the chemical elements are distributed in the material, which dictates the hardenability, or ability of the material to form martensite upon cooling.
The rate of cooling is also affected by the baking process. The faster the rate of cooling, the faster the material will reach its desired degree of hardenability. However, too fast a rate of cooling can be detrimental to the material and result in cracking or fractures due to thermal shock. Temperature and cooling time must be carefully monitored to ensure that the material reaches the desired degree of hardenability without thermal shock.
The baking hardenability of a material is also affected by the manufacturing process. Different manufacturing processes can produce different degrees of hardenability. The forging process can produce materials that can be heat-treated to higher degrees of hardenability than can materials manufactured by casting. The difference in hardenability between forging and casting can vary greatly, depending on the alloy and size of the component.
All these factors must be taken into account when manufacturing components that require a certain degree of hardenability. Failing to do so can result in components being unable to withstand the working environment they are intended for, resulting in failure. Baking hardenability is important when creating components that must be strong, resilient, and able to withstand the working conditions they will be subjected to. When properly accounted for, the baking hardenability of the material can result in components that are able to meet the required working parameters.
