Introduction
Heat treatment oil is a kind of specialty oil used in heat treatment processes. It is used to maintain heat treating parameters, improve surface properties, reduce part distortion and minimize corrosion or oxidation on the treatment surfaces. Heat treatment oils are divided into three categories according to their chemical compositions and applications. Heat treating oils are usually divided into mineral oils, vegetable oils and synthetic oils.
Mineral oil
Mineral oil, also known as paraffin oil, is the earliest kind of heat treatment oil that has been used. The mineral oils are refined from crude petroleum and are relatively cheap, making them the most popular and widely used heat treatment oil. Mineral oils are effective heat treatments since they provide moderations in temperature and can suspend buildups of powder, dust and dirt.
Vegetable oil
Vegetable oils are made by extracting oil from different kinds of plants. These oils, such as peanut oil and corn oil, have very little to no smell and are thermally stable. Vegetable oils are oxidatively stable and do not harden or smoke when heated. They are used in a range of heat treatments, such as carburizing, austempering and annealing.
Synthetic oil
Synthetic oils are chemical compounds made from complex mixtures of chemical compounds such as esters, polyol esters, silicones, and polyglycols. Synthetic oils are more thermally stable than mineral or vegetable oils and can resist oxidation at higher temperatures. Synthetic oils have higher dielectric strength than mineral oils, which makes them suitable for use in electric heat treatment processes. They also have better lubricity, which enables them to produce smoother parts with better surface finishes.
Conclusion
In conclusion, heat treatment oils can be divided into three distinct categories, mineral, vegetable and synthetic oils, according to their chemical compositions and applications. Mineral oils are the most widely used and are effective heat treatments. Vegetable oils have excellent oxidation stability and are particularly suitable for carburizing, austempering and annealing. And Synthetic oils are more thermally stable and can resist oxidation at higher temperatures, and they have higher dielectric strength and better lubricity which allows for better surface finishes.
