Advantages and Disadvantages of Stainless Steel Casting Process

Advantages and disadvantages of stainless steel casting process

 

Everyone in the casting industry knows a fact. That is the mechanical properties of stainless steel casting are higher than that of cast iron, but its casting performance is worse than that of cast iron. Stainless steel casting belongs to investment or precision casting, with relatively high melting point. The molten steel is easily oxidized, due to poor fluidity and large shrinkage rate. From a practical perspective, stainless steel casting is suitable for casting of various types and alloys.

 

Advantages and disadvantages of the stainless steel casting process are as below:

 

First, due to the poor liquidity of the molten steel, the wall thickness of the steel castings should not be less than 8 mm, in order to prevent the cold shut and misrun. The structure of the pouring system strives to be simple, and the sectional dimension is larger than that of cast iron. Adopt dry casting or hot casting, and the casting temperature should be appropriately increased to 1520-1600 ℃. The fluidity can be improved since the casting temperature is high with large superheat, thus the liquid stays for a long time.

 

However, if the pouring temperature is too high, it will cause defects such as coarse grains, hot cracks, pores and sand burning. Therefore, the casting temperature of small, thin-walled and complex casting should be at the melting point +150 ℃; and of large, thick-walled casting +100 ℃.

 

We must take these measures to prevent the occurrence of shrinkage holes and cracks in stainless steel castings. 1. Making the wall thickness uniform, and avoid sharp and right angle structures, 2. Adding sawdust to sand mold, and coke to sand core. 3. Adopting hollow sand core and oil sand core to change the deformability and permeability of the sand mold and core.

bronze casting & brass casting pipe

The Smelting Process of Copper Alloy

Metallurgical Microscope for grey iron casting and ductile iron casting

The Density of Ductile Iron

The density of ductile cast iron is approximately 7.3 g/cm3, or 7.3 kg/liter, or 119.6 g/cm3. However, due to the material grade and shrinkage level, the density has a certain range of variation.

In other words, if the quality of pig iron used by the iron foundry is better and the shrinkage rate is smaller, then the density of ductile iron will be higher. Otherwise, the density of ductile iron will be lower. Therefore, it ranges from 7.1 to 7.3 g/cm3.

Iron foundries usually estimate the weight of rough castings by calculating the volume of ductile iron, so the density will be used. However, you cannot judge the quality of castings by density alone.

There are more factors that will affect it, such as spheroidization rate and cooling rate. Hence, it will be reasonable within this range.

2025 Made in China and ONE BELT, ONE ROAD Policy Impact on Iron Foundry

With the implementation of “Made in China 2025” and “One Belt One Road” construction, the rapid development of all walks of life will be promoted. At the same time, the scale of China’s metal casting enterprises is also increasing year by year.

 

With the rapid development of various application fields, industry concentration has gradually increased, and product quality has continued to improve. This shows that the foundry industry has entered a medium-to-high-speed development stage.

 

The China (Beijing) International Foundry Exhibition will continue to be held at the China International Exhibition Center (new hall). In this way, it promotes the innovation and development of the foundry industry and promotes in-depth cooperation and exchanges between enterprises.

 

As a foundry with a history of more than 20 years, Yide Casting will take this opportunity to meet the needs of different customers in countries along the “Belt and Road” with high quality, high technology and high quality. Use better cast iron products to show the world the capabilities of China’s manufacturing.

What Is Iron Casting?

What Is Iron Casting?

What Is Iron Casting?

What Is Iron Casting?

Gray iron is the most common type of iron casting. Its properties are good, making it the preferred material for a wide variety of applications. Its properties include high hardness, tensile strength, compressive strength, fatigue strength, and resistance to corrosion. While this type of iron casting is highly versatile, its disadvantages include low tensile strength and low elongation. It is a great choice for applications that require high tensile strength.

Yide Casting produces medium and heavy castings with sectional sizes up to four inches. It is the only iron foundry to cast the full range of test bar sizes. Inoculated irons are stronger than base iron bars and have a greater scatter of tensile strength values. A six-inch-diameter section at this foundry shows tensile strength values below the SAE line. The tensile strength data on this material are based on the center portion of the 6-in.-pediatric sections.

Gray iron is highly resistant to cracks. Its mechanical properties are related to the percentage of graphite, and the carbon-equivalent value. The cooling rate and eutectic solidification interval play an important role in the tensile strength of gray iron. The section size affects the tensile strength. The ASTM Specification A 48 requires the selection of the test bar. If the gray metal has an elongation value of less than 0.5, it will be stronger. The failure section should be as large as possible.

When choosing an iron casting foundry, it’s important to choose one that processes ductile iron separately from gray iron. The former is more malleable and durable than ductile. However, some foundries process gray and ductile iron from the same charge material. For example, if a foundry was to process internal recycled scrap gray iron, the sulfur would remain in the material. The solution would be to use a reducing agent, such as CaO, to remove the sulfur.

Graphite is another element used in iron casting. Its gray color is a result of a process known as investment casting. The investment-casting process produces pieces with thin walls and is usually used for ductile iron. Centrifugal casting, on the other hand, has the advantage of reducing porosity and sturdiness of the finished part. In addition, the material is also more resistant to corrosion, which is a positive feature for the investment-grade material.

The gray iron found in commercial castings is the most affordable of the two types of iron. This type of iron has a high modulus of elasticity and is suitable for structural components that must be stiff. On the other hand, it is prone to thermal fatigue, so it is not recommended for housing and machinery bases. Its high tensile strength and elasticity to make it the best choice for these applications. It is a great choice for those who want to save money.