துருப்பிடிக்காத எஃகு துல்லியமான வார்ப்பு உற்பத்தியாளர்

துருப்பிடிக்காத எஃகு துல்லியமான வார்ப்பு முதலீட்டு வார்ப்பு என்றும் அழைக்கப்படுகிறது, சிலிக்கா சோல் செயல்முறை. இது ஒரு வார்ப்பு செயல்முறையாகும், இது பகுதிகளை குறைவாக வெட்டுவது அல்லது எந்திரம் இல்லாதது. ஃபவுண்டரி துறையில் இது ஒரு சிறந்த செயல்முறை தொழில்நுட்பமாகும், மற்றும் அதன் பயன்பாடு மிகவும் பரந்த உள்ளது. பல்வேறு வகைகள் மற்றும் உலோகக்கலவைகளை வார்ப்பதற்கு ஏற்றது மட்டுமல்ல, ஆனால் உற்பத்தி செய்யப்பட்ட வார்ப்புகளின் பரிமாண துல்லியம் மற்றும் மேற்பரப்பு தரம் மற்ற வார்ப்பு முறைகளை விட அதிகமாக உள்ளது. சிக்கலான, உயர் வெப்பநிலை எதிர்ப்பு, கடினமான செயலாக்க வார்ப்புகளை முதலீட்டு வார்ப்பு மூலம் அனுப்பலாம்.

Development history of investment casting methods
Modern investment casting methods were practically applied in industrial production in the 1940s. At that time, the development of aviation jet engines required the manufacture of heat-resistant alloy parts such as blades, impellers and nozzles with complex shapes, precise dimensions and smooth surfaces. Because heat-resistant alloy materials are difficult to machine, and the shapes of parts are complex, they cannot be manufactured by other methods. எனவே, it is necessary to find a new precision molding process, so learn from the ancient lost wax casting, after the improvement of materials and processes, modern investment casting methods have obtained important development on the basis of ancient processes.


எனவே, the development of the aviation industry has promoted the application of investment casting, and the continuous improvement and perfection of investment casting has also created favorable conditions for the aviation industry to further improve its performance. my country began to apply investment casting to industrial production in the 1950s and 1960s. அன்றிலிருந்து, this advanced casting process has been greatly developed, and has been widely used in aviation, வாகனங்கள், machine tools, ships, internal combustion engines, gas turbines, telecommunications equipment, weapons, medical equipment, and cutting tools. It is also used in the manufacture of arts and crafts.

What is investment casting?
The so-called investment casting process is simply to use fusible materials (such as wax or plastic) to make a fusible model (referred to as investment or model). Coat several layers of special refractory paint on it, dry and harden to form an integral shell, then use steam or hot water to melt the model from the shell, and then place the shell in the sand box. Fill it with dry sand molding around it, and finally put the mold into the roasting furnace for high-temperature roasting (if a high-strength shell is used, the demolded shell can be roasted directly). After the mold or shell is fired, molten metal is poured into it to obtain a casting.

The dimensional accuracy of investment castings is high, generally up to CT4-6 (sand casting is CT10~13, die casting is CT5~7). நிச்சயமாக, due to the complicated process of investment casting, there are many factors that affect the dimensional accuracy of castings. உதாரணத்திற்கு, the shrinkage of the mold material, the deformation of the investment mold, the linear change of the shell in the heating and cooling process, the shrinkage of the alloy, and the deformation of the casting during the solidification process. எனவே, although the dimensional accuracy of ordinary investment castings is relatively high, its consistency still needs to be improved (the dimensional consistency of castings using medium and high temperature wax materials should be improved a lot).

When pressing the investment mold, a pressure type with a high surface finish of the cavity is used, so the surface finish of the investment mold is also relatively high. கூடுதலாக, the shell is made of a refractory coating made of a special high-temperature resistant adhesive and refractory material, which is coated on the investment mold, and the inner surface of the cavity directly in contact with the molten metal has a high smoothness. எனவே, the surface finish of investment castings is higher than that of ordinary castings, generally reaching Ra.1.6~3.2μm.

The biggest advantage of investment casting is that because investment castings have high dimensional accuracy and surface finish, it can reduce CNC machining work. Just leave a little machining allowance on the parts with higher requirements, and even some castings only leave grinding and polishing allowances, so they can be used without mechanical processing. It can be seen that the use of investment casting method can greatly save machine tool equipment and processing man-hours, and greatly save metal raw materials.

Another advantage of the investment casting method is that it can cast complex castings of various alloys, especially high-temperature alloy castings. உதாரணத்திற்கு, the blade of a jet engine, its streamlined outline and cooling cavity, can hardly be formed by machining technology. Production with investment casting process can not only achieve mass production, ensure the consistency of castings, but also avoid the stress concentration of residual knife marks after machining.