15-5 PH Stainless Steel

15-5 PH stainless steel investment casting part

From our beginnings as a sand casting foundry in 1923, to our current position as a global full-service supplier, Barron Industries has developed an unsurpassed reputation for providing high-quality, 15-5 PH steel precision cast components.

15-5 PH Hardness Properties

15-5 PH stainless steel is used by manufacturers for high-precision machining, welding, forming, and casting. The material’s machining properties can further be enhanced with low-temperature heat treatment. 15-5 PH is particularly known for its high hardness. Depending on the heat treatment it receives, it can achieve hardness levels from 25 to over 33 on the Rockwell “C” scale.


15-5 PH steel’s chemical composition is carbon (0.07% maximum), Manganese (1%), Phosphorus (0.040%), Sulfur 0.030%), Silicon (1%), Nickel (Up to 5.50%),Copper (Up to 4.50%), and Chromium (Up to 15%). The chemical composition can be changed with heat treatment, but these elements and their percentages make up the base metal chemical properties.


Aside from its high strength, high hardness, and excellent corrosion resistance, there are other advantages to using 15-5 PH. In terms of investment castings, the finished product that emerges from the mold will have an excellent surface finish. The material also has low porosity and inclusion counts compared to other stainless steel grades. This means the material is less likely to fracture or crack during machining and finishing. It’s also less likely to encounter fatigue failure during in-field use.


There is no shortage of applications for 15-5 PH stainless steel investment castings. These types of castings are widely used across the spectrum of defense, aerospace, marine and petrochemical applications where lightweight, high-strength and corrosion resistance is needed.

15-5 PH Stainless Steel in the Defense Industry

15-5 PH stainless steel is used in the defense industry when lightweight and extremely high-strength is required along with corrosion resistance that can’t be achieved by utilizing alloy steel grades such as traditional armor steel or quench and tempered alloy steel. Examples are components that will be exposed to the elements while taking very heavy loads such as shock mounts for severe service, alternator brackets or engine mounting brackets.

15-5 PH Applications in the Aerospace Industry

This type of stainless steel is comparable to the extremely popular 304 stainless steel in corrosion resistance and machinability. However, it is harder with higher mechanical  properties. This makes it better for heavy-duty applications than the commonly used 304 stainless steel. 15-5 PH Stainless Steel castings are frequently used in aircraft door hinges, control surface attachment points, servo drive housings, landing gear, and other highly-stressed attachment joints. 

15-5 PH Applications in the Marine Industry

The advantage of 15-5 PH is its high strength and corrosion resistance and in the H1350M over aged condition, you can reach elongation properties up to 20 percent.

As an example, the surface piercing offshore race boat propellers that are seeing 4,000 HP driving them are cast out of 15-5 PH stainless steel that receive an H1350M over aging heat treat. When the blade is subjected to the extreme torque and HP, it’s actually deforming considerably at some points but then springs back to its original shape.

Contact Barron Industries Today

Barron Industries is a NADCAP-accredited, and AS9100D Certified manufacturer and supplier of precision castings. With close to 100 years of Metalcasting experience ,we have the engineering expertise, machining capabilities, and know-how to handle any requirement.

If you have questions about 15-5 PH stainless steel or would like to request a quote, please fill out our online form.