Novel high temperature resistant ductile iron article for furnace

Abstract

The invention relates to novel high-temperature resistance magnesium iron matter used for a furnace, which belongs to the field of metallurgical industry, in particular to novel high-temperature resistance magnesium iron material, currently, the general high-temperature resistance material adopts Ni and Cr alloys which are expensive, thereby the cost is high. The novel high-temperature resistance magnesium iron material mainly adds 20-24 percent of Al in magnesium iron so as to achieve the purpose of high-temperature resistance. The magnesium iron adopts main materials of pig iron, scrap steel, rear-earth, calcium alloy (Ca is equal to 28 percent), fluorite, calcium carbonate and borax, and a medium-frequency induction furnace or a crucible resistance furnace is adopted as a device. The process comprises the following steps: firstly, the borax and aluminum ingot are put in a graphite crucible in the crucible resistance furnace, the aluminum is overheated to 800-850 DEG C, and then the pig iron, the fluorite and the calcium carbonate are put into the middle-frequency induction furnace, after that, the heating is stopped when the pig iron is molten to 1480-1520 DEG C, and finally, the scrap steel is added till becoming red; secondly, the rear-earth (the addition quantity is 1.0-1.4 percent) which is preheated to 500-600 DEG C and the calcium carbonate (the addition quantity is 0.4-0.6 percent) are strewed on the surface of aluminum liquid and are then poured into the middle-frequency induction furnace, and molten iron is overheated depending on the heat produced through the reaction of aluminum and iron so that the scrape steel is molten; at the moment, the temperature of the alloy liquid is more than 1600 DEG C, and then the processes of stirring, stewing and slag-off are carried out after the reaction is steady; and the alloy liquid is discharged from the furnace and casted till the temperature reaches 1400-1420 DEG C.

Description

technical field [0001] The invention belongs to the field of metallurgical industry, in particular to a novel cheap heat-resistant ductile iron material. Background technique [0002] Most of the current furnace heat-resistant materials are casted with Ni-Cr high-alloy materials. Ni and Cr resources are scarce, raw materials are expensive, and the production cost of castings is also high, so the application and promotion are greatly restricted. Some high-silicon heat-resistant cast irons cannot meet the conditions of use in environments above 900 ° C. High-silicon balls Although the heat-resistant temperature of iron and high-chromium cast iron can exceed 950°C, they are very brittle and easy to break at room temperature. Contents of the invention [0003] The invention is mainly a high-temperature-resistant new material with 20%-24% Al added to the ductile iron. The heat-resistant temperature can reach 1100°C, and it has good high-temperature mechanical properties and ox...

AI Technical Summary

Problems solved by technology

Ni and Cr resources are scarce, raw materials are expensive, and the production cost of castings is also high, so the application and promotion are greatly restricted. Some high-silicon heat-resistant cast irons cannot meet the conditions of use in environments above 900 ° C. High-silicon balls Although the heat-resistant temperature of iron and high-chromium cast iron can exceed 950 ° C, they are very brittle and easy to break at room temperature