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Analysis of the causes and solutions of loose materials in stainless steel casting









Stainless steel casting, whether it is a flat ingot or a round ingot, often causes problems of porosity and loose defects in the production. The pores and looseness are like twin sisters, often accompanied by a living, which brings a lot of trouble to aluminum processing. The presence of a circular hole in a stainless steel cast structure is called a pore. It is a bubble defect formed by the deposited gas in the ingot during the cooling and solidification of the metal liquid. Looseness is the process of solidification in the stainless steel casting structure. Due to the stainless steel in the liquid and solidified state, the volume is not well replenished to produce a dispersion hole. The main factor of pore formation: the gas in the melt in the solution is in a saturated state, and there is a large amount of non-metal slag in the solution. When the gas floats slowly during the casting process, the bubbles will stay in the ingot to generate pores.
There are several reasons for analyzing looseness:
1. The melt is overheated. 2. The gas content in the melt is too high. 3 casting temperature is too low. 4. The strength is small. The casting speed is too fast. 5. The funnel supply is uneven. 6. The oven is not thorough. The furnace shutdown time is too long. 7. Tools and refined gases. Solvents are damp or incomplete. 8. High magnesium alloy coverage is not good.
Stainless steel casting porosity and porosity are one of the most common defects, stainless steel smelting and casting technology (process code); are developed around the porosity and porosity defects. How to solve the problem of porosity and loose defects?
Take several measures:
1. Control the chemical content of impurities (reducing non-metallic inclusions) 2. It is to change the solid material to liquid material (shortening the smelting time) 3. It is to strengthen the refining and degassing 4. It is to change the original small ingot size to large The ingots (to reduce the casting speed and change the over-belt size) result in losses.
Causes of stomata:
1. Furnace overhaul or medium repair. Drying after long-term shutdown is not complete. 2. The raw materials are damp. There is oil and water. 3. The quality of the lubricant is not good. 4. The melt is overheated in the furnace. 5. The tool is completely dry at the end. 6. Gas moisture is too large. 7. The smelting time is too long.
Looseness is generally divided into two types: one is the looseness produced between the shrinkages, and the other is the looseness formed by the removal of the dissolved gas. The main factor in the formation of looseness is related to the gas content of the melt and the size, shape and structure of the over-belt when the ingot is formed.


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