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What is Stainless Steel Investment Casting
Stainless steel investment casting is, as the name suggests, the process of casting stainless steel alloys using investment casting. It is a process in which melted stainless steel is poured into molds to cool and harden. So, a solid stainless steel part with the right shape was made.
Stainless steel is a popular material used for casting products. Its best feature is that it doesn’t rust or corrode.
Investment casting is a way to shape metal. First, a wax pattern is made, and then a ceramic shell is put around it to make a ceramic mold. The ceramic shell is used as a mold when the wax is melted. The mold is then filled with molten stainless steel to make a casting. Some investment castings may need to be machined again after the metal has hardened and the mold has been taken off.
Materials Grade Used in Stainless Steel Investment Casting
Low-carbon steel is another name for stainless steel. It has at least 10% chromium in it, which causes a film of chromium oxide to form. This film gives stainless steel its unique ability to resist corrosion and heal when oxygen is present. The metal is easy to shape, so it can be used to make parts that are the right size have a good finish, and have complex shapes.
Austenitic Stainless Steel
The 300 series is the most common type of stainless steel alloy. It is a chromium-nickel alloy that is not magnetic. This group of alloys is very resistant to corrosion, but heat treatment does not make them stronger. The 304 alloys are known for having very clean standards. The 304-L and 316-L alloys are low in carbon, which makes them softer but more resistant to corrosion and able to handle high-temperature processes for finishing
Duplex Stainless Steel
Duplex stainless steel has qualities of both ferritic and austenitic stainless steel. People often use these alloys in places where pitting and corrosion are a problem, especially where it’s cold. Benefits include improved strength, toughness, flexibility, and corrosion resistance.
Ferritic Stainless Steel
This alloy has a very low amount of carbon and more than 12% chromium. Its molecular grain structure and chemical make-up are different from other types of stainless steel. It can’t be made stronger by heating it.
Martensitic Stainless Steel
Different grades of martensitic stainless steel alloys are made up of chromium, a small amount of carbon, and other elements. Hardening and tempering can improve the mechanical properties of a casting made of this stainless steel alloy. This alloy is good for when you need resistance to corrosion and oxidation, as well as either high strength at low temperatures or resistance to creep at high temperatures.
Precipitation Hardening Stainless Steel
During this process, heat is used to make the alloy very strong. The strongest alloy in the family of stainless steels is made by precipitation hardening, and it is used for parts that can’t bend.
7 Important Benefits of Stainless Steel Investment Casting
High-Quality Surface Finish
Compared to other casting processes, the wax method stainless steel investment casting provides a high-quality surface finish. When it comes to tolerances, investment casting is more accurate than other casting methods. Even more so when compared to things that are made by sand casting, welding, or forging. This makes it possible to do less or no machining and gives the surface a better finish. And sometimes, surface finishing is not needed.
It can also put complex text or a LOGO outside the product. To make a product more valuable.
Precision and Tight Tolerances
Precision stainless steel castings are a specialization of investment casting, which goes by the name “precision casting” in general. Tolerance levels of CT5-CT6 are easily achieved, allowing the manufacturer to forego additional machining required by competing manufacturing processes.
While casting, a small machining allowance is allocated to reduce the post-cast machining amount, even if tighter tolerances are required. Therefore, it is safe to say that net shape or nearly net shape products are possible through investment casting. However, this is not always achievable with other casting methods.
Greater Heat Resistance
Investment casting can be done with many different kinds of materials. Stainless steel is known for its high-temperature resistance, and this property makes it one of the best materials in the construction and industrial industries. And is considered the best material for investment casting because of its impressive heat resistance properties.
The different kinds of stainless steel for investment casting and how they handle heat are as follows:
304 Steel – this type of steel has lots of chromium and nickel in it. Thus, it does not corrode or rust. The hottest temperature it can handle is 8700C.
309 Steel – You can use this to make high-temperature tools and machines, such as oven firebox sheets, liners, and parts for steel furnaces. Steel can get as hot as 980 degrees Celsius for short periods of time and 1097 degrees Celsius for long periods.
310 Steel – The most important thing about the 310 steel is that it stays strong even when it gets very hot. This 310 steel is used to make heat exchangers, burner tips, heat treatment baskets, flare tips, jigs, and refractory anchors, among other things. The highest temperature that 310 steel can reach for short periods is 1035 degrees Celsius, and its highest temperature for long periods is 1150 degrees Celsius.
316 Steel – It also has carbon, molybdenum, manganese, and silicon in its make-up. Not only is 316 steel can resist corrosion, but it is also resistant to many liquids. This steel is used for things like medical equipment, tools and equipment for the sea, and making and storing chemicals. Since 316 steel is a lot like 304 steel, it can handle high temperatures just as well.
312 Steel – It is used to make aircraft exhausts, bellows, welded processing screens, and parts for furnaces, among other things. 321 steel can get as hot as 870 degrees Celsius for short periods of time and 925 degrees Celsius for long periods.
Corrosion Resistance
The best thing about stainless steel is that it doesn’t rust or corrode. Unlike some other materials, stainless steel investment castings already have a layer of chromium oxide that makes them very resistant to corrosion. Because they don’t rust, stainless steel castings are great for military, medicine, and industrial use.
Fast Production
The use of investment castings reduces the amount of time spent on labor and make shorter turnaround times because they require a significantly reduced how much work a machine does after the casting has been completed.
Affordable
The process of investment casting requires equipment that is both less costly and inherently less dangerous, which enables costs to be maintained at a level that is more manageable.
Flexible Design
Freedom of design is typically regarded as one of the primary benefits of investment casting.
It is especially ideal for complex parts, even parts with complex internal shapes, and has a wide range of applications. Aluminum alloy, cast iron, and non-ferrous alloys are some of the most frequently used investment cast materials, but it offers almost unrestricted freedom in terms of the investment cast materials that can be used. The use of the process to work with high-temperature alloys is particularly appealing.
It possesses a high degree of adaptability and is not constrained by the casting’s dimensions, thickness, or shape complexity. There is also flexibility in the production methods.
Stainless Steel Investment Casting Applications
Stainless steel castings are used in a wide range of industries, especially those that work in harsh environments. This is because stainless steel has unique physical properties. Here are the main ways that stainless steel casting is used:
Food Machinery
Because it doesn’t rust, stainless steel is used to make almost all of the equipment used to process food. Usually, many stainless steel parts are used to put together equipment like this. There are many ways to make these stainless steel parts, like casting, welding, forging, machining from a plate, and so on.
Casting is the most flexible of these ways to make parts for food processing machines with complicated shapes. So, a lot of food machinery uses castings made of stainless steel. Components for metal grinders, coffee machines, and other food machines are typical examples of parts made by casting stainless steel.
Marine Application
Stainless steel castings are used in marine applications that need strong parts with very high resistance to heat, wear, and corrosion. CFS foundry uses many stainless steel alloys to make parts for recreational, government, and commercial marine vessels. Marine castings made of stainless steel can be polished to a mirror finish to make them resistant to corrosion and wear. .
Some new investment castings made of marine-grade stainless steel that are machined and electro polished are now on the market. This would give great savings to the customers, around 30% of what they are currently spending.
Marine Application
Stainless steel castings are used in marine applications that need strong parts with very high resistance to heat, wear, and corrosion. CFS foundry uses many stainless steel alloys to make parts for recreational, government, and commercial marine vessels. Marine castings made of stainless steel can be polished to a mirror finish to make them resistant to corrosion and wear. .
Some new investment castings made of marine-grade stainless steel that are machined and electro polished are now on the market. This would give great savings to the customers, around 30% of what they are currently spending.
Medical Equipment
Stainless steel casting can be used to make a lot of different parts for medical instruments. Manufacturers work with many types of stainless steel, like stainless steel 304(L), stainless steel 316(L), and more, to make custom parts that meet the tight tolerances and precise dimensions needed for medical applications.
Stainless steel cast is used in manufacturing parts for medical OEMs like dental and surgical tools, operating tables, implantable components, other operating room equipment, wheelchairs, MRI machines, stretchers, X-ray machines, similar products, injury stabilizing devices, and more.
Pipe Fittings
Fittings like tees, elbows, close nipples, bushings, and so on are often made of cast stainless steel. Aside from casting, there are other kinds of machining you can do from it, like making holes or threads.
When buying pipe fittings, think about how they will be used. Stainless steel 316 is better than stainless steel 304 in general. No matter how strong or resistant to rust it is.
Stainless Steel Investment Casting Company
Find the best company to help you with your next stainless steel investment casting project, whether you’re looking into making a new product or putting an old one into production. You can find a lot of stainless steel investment casting companies that work with a wide range of industries to make high-quality metal parts. Before you work with them, you can ask for a quote.
Leisheng Machinery is a professional Investment Casting Foundry in China, Providing Provide Investment Casting Solutions & Services Since 2006. From simple cast steel components to highly complex alloy casting that all supported. Contact Us to Get Quotation Now!