Stainless steel is one of the most widely used materials in various industries, including consumer products, construction, and aerospace. However, with so many stainless steel types available, choosing the right one for your needs can be confusing. In this blog post, we will discuss the differences between two specific types of stainless steel: 15-5 PH and 17-4 PH.
Difference Between 15-5 and 17-4 PH Stainless Steel
Composition
The primary difference between 15-5 PH and 17-4 PH stainless steel is in their composition. 15-5 PH stainless steel contains 15% chromium, 5% nickel, and 3% copper, while 17-4 PH stainless steel contains 17% chromium, 4% nickel, and 3% copper. Additionally, 17-4 PH contains 4% molybdenum, which 15-5 PH does not have.
Hardness and Strength
Due to the difference in composition, the hardness and strength of 17-4 PH stainless steel are higher than 15-5 PH stainless steel. 17-4 PH has a higher tensile strength of around 200 ksi, while 15-5 PH has a tensile strength of around 190 ksi. Furthermore, 17-4 PH has a yield strength of around 175 ksi, while 15-5 PH has a yield strength of around 170 ksi.
Corrosion Resistance
Both 15-5 PH and 17-4 PH stainless steel have excellent corrosion resistance. However, 15-5 PH stainless steel is more resistant to stress corrosion cracking caused by the combined effects of tensile stress and a corrosive environment. In contrast, 17-4 PH stainless steel is more susceptible to stress corrosion cracking and requires careful handling to avoid this problem.
Applications
Both 15-5 PH and 17-4 PH stainless steel are used in various applications, including aerospace, defence, and oil and gas industries. 15-5 PH stainless steel is often used in applications that require good corrosion resistance, high strength, and toughness, such as aircraft structural components, gears, and valves. In contrast, 17-4 PH stainless steel is commonly used in applications that require high strength and corrosion resistance, such as aerospace components, oil and gas equipment, and medical instruments.
Cost
Finally, the cost difference between 15-5 PH and 17-4 PH stainless steel can be significant. Generally, 17-4 PH stainless steel is more expensive than 15-5 PH due to its higher chemical composition and superior properties. However, the cost difference may vary depending on the supplier and the material required.
Conclusion:
In summary, the choice between 15-5 PH and 17-4 PH stainless steel depends on several factors, including the specific application, corrosion resistance needs, and the cost budget. Although both types of stainless steel offer high strength and excellent corrosion resistance, 17-4 PH stainless steel is superior to 15-5 PH in hardness and tensile strength. At the same time, 15-5 PH stainless steel offers better resistance to stress corrosion cracking. Therefore, it’s important to consider these differences carefully when selecting the right material for your project and consult an experienced provider if necessary.
