SALT BATH HEAT TREATMENT PROCESS
Currently, heat treatment has been successful predominantly using atmospheric methods. Although these methods have been effective, an alternate method of treating has offered an upgrade on the process. The alternate process, shows increases in time efficiency, quality of the end product and most importantly, is more environmentally friendly.
The Salt Bath process proves more efficient in energy usage allowing a more suitable and environmentally friendly process. Atmospheric furnaces use only 60% of power for the actual treatment and leaves 40% of wastage energy, the salt bath immersion uses between 93% -97% heating the parts. The Salt bath heat treats parts through conduction. The full immersion of the parts in the liquid bath allows it to be treated equally as the core of the part rises in temperature at almost the same rate as its surface due to the ready and stable source of heat provided by the method. The effectiveness of the Salt bath being able to maintain an equilibrium rate of heat absorption improves time efficiency and can shorten the process by up to 5 times while also providing a superior quality end product.
Uniform heating together with the density and the medium of the molten salt provides greater support for the total part. These factors minimize distortions of the part such as bending or sagging. The uniformity of the heat at the equilibrium rate supported by the layer of solidified salt coated around the part helps reduce the risk of initial rapid heating that could result in thermal shock. As the salt melts, the gradual and uniform heating of the part helps prevent brittleness and distortion.
Quality of the end product is superior due to the elimination of the risk factors of atmospheric treatment. A salt bath provides a vacuum treatment process. This way, gasses such as carbon-dioxide, oxygen and water vapour are not a threat to causing scale formation. Parts immersed in salt are also retrieved with a thin layer of solidified salt, which can be easily washed off, but also provides further protection from the formation of damaging oxide scales.
The Salt Bath process proves more efficient in energy usage allowing a more suitable and environmentally friendly process. Atmospheric furnaces use only 60% of power for the actual treatment and leaves 40% of wastage energy, the salt bath immersion uses between 93% -97% heating the parts. The Salt bath heat treats parts through conduction. The full immersion of the parts in the liquid bath allows it to be treated equally as the core of the part rises in temperature at almost the same rate as its surface due to the ready and stable source of heat provided by the method. The effectiveness of the Salt bath being able to maintain an equilibrium rate of heat absorption improves time efficiency and can shorten the process by up to 5 times while also providing a superior quality end product.
Uniform heating together with the density and the medium of the molten salt provides greater support for the total part. These factors minimize distortions of the part such as bending or sagging. The uniformity of the heat at the equilibrium rate supported by the layer of solidified salt coated around the part helps reduce the risk of initial rapid heating that could result in thermal shock. As the salt melts, the gradual and uniform heating of the part helps prevent brittleness and distortion.
Quality of the end product is superior due to the elimination of the risk factors of atmospheric treatment. A salt bath provides a vacuum treatment process. This way, gasses such as carbon-dioxide, oxygen and water vapour are not a threat to causing scale formation. Parts immersed in salt are also retrieved with a thin layer of solidified salt, which can be easily washed off, but also provides further protection from the formation of damaging oxide scales.
