The stainless steel investment casting process in CFS Foundry can be used to produce stainless steel products in different grades. To have a better understanding, here we would like to share the basic differences of some main grades.
304 Stainless Steel
304 stainless steel is one of the most widely used stainless steel alloys due to its excellent corrosion resistance and high temperature resistance. It contains 18% chromium and 8% nickel, which gives it its corrosion-resistant properties. 304 stainless steel is often used in food processing equipment, chemical processing equipment, and architectural applications due to its aesthetic appeal.
304L Stainless Steel
304L stainless steel is a low-carbon version of 304 stainless steel, with a maximum carbon content of 0.03%. This makes it more resistant to sensitization, which is a type of corrosion that can occur when stainless steel is heated to high temperatures. 304L stainless steel is often used in welding applications due to its low carbon content.
316 Stainless Steel
316 stainless steel is a molybdenum-bearing stainless steel alloy that offers improved corrosion resistance compared to 304 stainless steel. It contains 16-18% chromium, 10-14% nickel, and 2-3% molybdenum. The addition of molybdenum makes 316 stainless steel more resistant to pitting and crevice corrosion in chloride environments. It is often used in marine applications, chemical processing equipment, and medical devices.
316L Stainless Steel
316L stainless steel is a low-carbon version of 316 stainless steel, with a maximum carbon content of 0.03%. This makes it more resistant to sensitization and intergranular corrosion. 316L stainless steel is often used in welding applications and in environments where high corrosion resistance is required.
17-4 Ph Stainless Steel
17-4 PH stainless steel is a precipitation-hardening stainless steel alloy that contains 15-17% chromium, 3-5% nickel, and 3-5% copper. It also contains 0.15-0.45% carbon and 3-5% molybdenum. 17-4 PH stainless steel can be heat treated to achieve high strength and hardness, making it ideal for applications such as aerospace components, pump shafts, and nuclear waste casks.
2205 Duplex Stainless Steel
2205 stainless steel is a duplex stainless steel alloy that contains 22% chromium, 5-6% nickel, and 3% molybdenum. It also contains small amounts of nitrogen and manganese. The duplex structure of 2205 stainless steel gives it high strength and excellent corrosion resistance in chloride environments. It is often used in chemical processing equipment, pulp and paper mills, and oil and gas applications.
Comparison of Stainless Steel Alloys in Investment Casting
When choosing a stainless steel alloy for investment casting, there are several factors to consider, including corrosion resistance, strength, and cost. The table below compares several different stainless steel alloys commonly used in investment casting.
| Stainless Steel Alloy | Corrosion Resistance | Strength | Cost |
| 304 | Excellent | Moderate | Low |
| 304L | Excellent | Moderate | Low |
| 316 | Excellent | Moderate | Moderate |
| 316L | Excellent | Moderate | Moderate |
| 17-4 PH | Excellent | High | High |
| 2205 | Excellent | High | High |
As the table shows, all of these stainless steel alloys offer excellent corrosion resistance. The choice of alloy will largely depend on the specific application and the required strength. 304 and 304L stainless steel are good choices for applications where cost is a concern and moderate strength is sufficient. 316 and 316L stainless steel offer improved corrosion resistance and moderate strength, making them ideal for marine and chemical processing applications.
17-4 PH and 2205 stainless steel offer higher strength and excellent corrosion resistance, but at a higher cost. 17-4 PH stainless steel is ideal for applications where high strength and hardness are required, such as aerospace components and pump shafts. 2205 stainless steel is a good choice for applications where high strength and corrosion resistance are required, such as chemical processing equipment and oil and gas applications.
In addition to these factors, the choice of stainless steel alloy for investment casting will also depend on the casting process used. Some stainless steel alloys may be more difficult to cast than others, or may require different casting parameters to achieve optimal results.
CFS Foundry is one of the largest stainless steel casting companies in China. By our decades of experience with stainless steel investment casting, we can assure you high quality castings, which are produced in a very efficient manner. Want to choose a stainless steel casting company for your project? Pls feel free to send us your drawings!