Home page

Changes of Internal Elements in 304 Stainless Steel Precision Casting Process

Release time:

2023-11-13

The metallographic structure of 304 stainless steel containing 18% chromium and 8% nickel after cooling should be F + A + carbide, but its eutectoid transformation can not occur before casting cooling conditions, thus obtaining A + carbide. When chromium carbide appears in steel, its corrosion resistance is greatly reduced, resulting in poor chromium layer, so that the chromium passivation film is damaged, so intergranular corrosion is greatly increased. In order to eliminate the carbide in the cast steel, on the one hand, quenching treatment can be carried out; on the other hand, the right amount of titanium and niobium can be added to the steel to form titanium carbide or niobium carbide, thus avoiding the formation of chromium carbide and poor chromium layer. In order to produce stable titanium carbide or niobium carbide, the amount of titanium added should generally be greater than 5 times the carbon content, and the amount of niobium added should generally be more than 8 times the carbon content. In addition, stainless steel smelting is generally used alkaline furnace lining, because the acidic lining will make the steel mixed with small SiO2 inclusions, so that the plasticity and toughness of the steel is reduced a lot.

For smelting 304 stainless steel precision casting steel materials, it is required to remove impurities such as oil and dirt. The returning furnace material must spray sand and oxide skin, and can be put into furnace for smelting only after being clean. After the molten pool of steel is completely melted, low-carbon ferromanganese and low-carbon ferrosilicon are put into alloying and pre-deoxidation as required.

The order, time and method of addition of various alloying elements have a great relationship with the recovery rate. The addition sequence and time of alloy elements are determined according to the following requirements: the added alloy elements should be melted as soon as possible to make the composition uniform; The recovery rate of alloy elements should be high, that is, to reduce the burning loss of alloy elements and not to increase the impurities in steel; Impurities and gases brought by alloy elements should be removed.

Stainless steel precision casting material determines the performance of castings

What are the cleaning methods of stainless steel precision casting?

Stainless steel precision casting material determines the performance of castings

What are the cleaning methods of stainless steel precision casting?

Latest information

Stainless steel precision casting material determines the performance of castings

Stainless steel light alloy with its low density, high specific strength, corrosion resistance and other excellent characteristics, will be more widely used in aviation, aerospace, automotive, machinery and other industries. Especially in the automotive industry, in order to reduce fuel consumption and improve energy efficiency, it is a long-term development trend to replace steel castings with aluminum and nickel alloy castings. It focuses on the non-polluting, efficient and easy-to-operate refining technology, metamorphic technology, grain refinement technology and furnace rapid detection technology.

2023-11-13

Stainless steel precision casting material determines the performance of castings

The output of cast steel is relatively stable, while the quality, variety, performance and the proportion of alloy steel and special steel of cast steel are increasing. The use of various refining processes and technologies to develop new cast steel materials can improve the strength, toughness and special properties of the material.

2023-11-13

Changes of Internal Elements in 304 Stainless Steel Precision Casting Process

2023-11-13