Within demanding industrial situations, tools are frequently exposed to harsh environments. Among the most problematic situations is being exposed to very high temperatures. Having the right type of tool steel for such applications is more than merely convenience; it is a vital decision which will play a critical role in the tool’s longevity, safety, performance, and ultimately, its cost-effectiveness. Making the wrong choice could well result in premature tool failure, compromised product quality, and costly downtime. However, because there are many different types of tool steels, having a thorough understanding of the properties of different tool steels and the demands of the application, will make decision-making much easier.
The Challenge
The main issue, in applications that involve high temperatures, is being able to maintain the steel’s mechanical properties – wear resistance, hardness, and strength – when it is subjected to high heat. When temperatures rise, ordinary steels can become vulnerable to getting deformed and oxidized, lose their cutting edge, and even soften. This means that the key to selecting the best tool steel is in being able to identify grades which have been specifically engineered for thermal stability. Although there are applications which may initially consider various types of tool steel, including those which are sourced from high speed steel suppliers, extreme heat often requires a different class of materials.
Selection Considerations
There are a number of vital factors that must be considered during the process of selecting the best tool steel. The most obvious is operating temperature as it dictates the required “hot hardness” or the tool steels’ ability to maintain its strength and hardness when exposed to high heat which is something that is not present in cold work steel. Load and stress, another factor, demand sufficient toughness and hot strength, along with “creep resistance” or the tool steels’ ability to resist getting permanently deformed because of prolonged and constant exposure to high heat. Another crucial factor is wear resistance at elevated temperatures, and the ability to withstand rapid and significant changes in temperature without fracturing or losing structural integrity or thermal shock resistance. Lastly, resistance to oxidation prevents the tool steels’ surface degradation.
Considering the above factors, there are certain classes of tool steels that are preferred for high-temperature applications. Hot-work tool steels are specifically designed for such conditions. While cold work steel are best used in applications where the temperatures are relatively low, it is not suited for the intense heat encountered in die casting or forging.
Although high speed steel suppliers offer materials known for outstanding cutting ability and some degree of red hardness, their main application is not typically in the highest temperature ranges where heavy loads and prolonged exposure are common. In such demanding situations, hot work steels are the better solution. It is important to understand such distinctions when choosing the best tool steel for high-temperature applications.
Ultimately, choosing the best tool steel for high temperature applications require a careful evaluation of the operating conditions as well as the limitations of various tool steel types. When exploring options from reputable suppliers may be relevant for certain special applications, and understanding the properties of cold work steel helps it ruling it out of high-temperature applications, the focus must remain on tool steel grades which are specifically designed to withstand thermal stress and maintain their integrity to ensure better performance and longevity.