Production method of vermicular graphite cast iron

Abstract

The invention relates to a production method of a cast iron, and especially relates to a production method of a vermicular graphite caste iron. The method comprises the following steps: (1) feeding: adding titanium iron into a furnace along with the first batch of furnace charge, wherein the titanium iron accounts for 0.1 to 0.3% of the weight of the furnace charge; (2) smelting: controlling the temperature below 1380 DEG C during the smelting process, wherein the sampling temperature is 1460 to 1480 DEG C, and the overheating temperature is 1500 to 1510 DEG C; (3) embedding: adding a vermiculizer in one side of a vermicular bag, firmly pressing, covering the vermiculizer with an inoculant, then covering the inoculant with 1% to 2% of steel debris until the inoculant is firmly and fully covered, placing 0.5% to 0.8% of copper on the end that molten iron flows in; (4) rapidly discharging iron for one time, wherein the iron discharging temperature is 1470 to 1490, an inoculant slot is not used, and the molten iron is introduced into the system from the side that is not provided with the vermiculizer; (5) carrying out vermicular reactions, and finally removing the slag after the vermicular reactions. The method is unique, and the equipment for on-the-spot metallography detection is not needed to achieve the stable vermicular graphite rate.

Description

technical field [0001] The invention relates to a method for producing cast iron, in particular to a method for producing vermicular graphite cast iron. Background technique [0002] As a material whose properties are between gray cast iron and nodular cast iron, compacted graphite cast iron is relatively difficult to produce, and research on compacted graphite cast iron in foreign countries is relatively early, and the development of compacted graphite cast iron technology began in the 1990s In Europe, the first mass production of cylinders was in 1999. Domestic research on vermicular graphite cast iron was relatively late. In the past few years, domestic standards stipulated that the creep rate of test blocks should reach more than 50%. Recently, with the development of vermicular iron in my country, Revise the standard of creep rate to more than 80%, but there are relatively few domestic manufacturers of vermicular cast iron in batches, and the creep rate [0003] It is di...

AI Technical Summary

Problems solved by technology

Defects in the existing technology: firstly, in terms of technology, the existing technology for producing vermicular graphite cast iron, it is more common to perform vermicular treatment by embedding and flushing, and the embedding materials are usually rare earth silicon-magnesium alloy and rare earth magnesium alloy + Ti two

These two methods require that each parameter and the addition amount of vermicular agent and inoculant must be calculated according to the S content in front of the furnace, and the amount of iron tapping is required to be accurate. Due to the narrow range of Mg content in the production of vermicular graphite cast iron, and the interaction between Ti and Mg The range of worm graphite produced by the action is also very narrow, so there are certain defects in the way of embedding treatment, and the vermicular rate cannot be well and stably controlled

[0007] So far there is no way to overcome the above

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