Preparation method of magnetic response green sand cavity with excellent collapsibility

Abstract

The invention discloses a preparation method of a magnetic response green sand cavity with excellent collapsibility, and relates to the technical field of molding sand processing. The preparation method comprises the specific steps of: (1), dissolving antimony potassium tartrate with deionized water, sequentially adding PVP-K30 and thioacetamide, pouring the mixture into a reaction kettle laid with hydroxyapatite nanowires, and thus obtaining pretreated hydroxyapatite; (2) carrying out dry grinding, mixed grinding and sand production on the raw materials, then putting the raw materials in a drying oven for heat treatment, and molding a semi-finished green sand cavity through a high-pressure molding machine; and (3) carrying out modification treatment on nano ferroferric oxide particles by using oleic acid, adding silicone oil to form a magnetic fluid, and dipping the semi-finished green sand cavity in the magnetic fluid to obtain a finished green sand cavity meeting the requirements. The magnetic response green sand cavity has excellent collapsibility, the surface quality of a casting formed by casting is high, the percent of pass and the yield of the casting are improved, the production cost is reduced, and the magnetic response green sand cavity has extremely high economic benefits and can be widely used.

Description

technical field [0001] The invention belongs to the technical field of molding sand processing, and in particular relates to a method for preparing a magnetically responsive green sand cavity with excellent collapsibility. Background technique [0002] Green molding sand, also known as green molding sand, refers to the sand mixture that uses bentonite as a binder in foundry production, and then mixes it with water and other additives. It can be used for molding and core making. The sand mold does not need to be dried and can be poured directly. At present, the green sand molding process still occupies a major position in the foundry production, and the performance of the sand mold directly determines the quality of the casting. Among them, the air permeability of green sand has the most direct impact on the defects of castings such as pores, sticky sand and sand holes. The green sand mold cavity produced by the existing green sand molding has poor collapsibility. After the ...

AI Technical Summary

Problems solved by technology

The green sand mold cavity produced by the existing green sand molding has poor collapsibility. After the casting is completed, the vibrating screen needs to use relatively high-power vibration to cause the green sand mold cavity to collapse, which not only causes waste of energy, but also makes production Large vibration noise generated in the area

For example, Chinese patent CN2016103617657 discloses a kind of easy-to-collapse damp mold sand. The technical solution adopts nano-attapulgite soaked in sodium bicarbonate solution and titanium dioxide soaked in succinic acid solution, combined with modified sodium bentonite, In order to further improve the performance of green mold sand, it can avoid the problems of sand inclusion, depression, scarring and box collapse caused by the expansion defect of green mold sand, and add lignocellulose to improve the compressive strength of green mold sand. With the addition of brown corundum powder, it can not only improve the collapsibility of the green sand, thereby improving the surface quality of the casting, but also improve the durability of the green sand and save a lot of production costs; It is easy to form large agglomerates. When recycling, it needs to be crushed manually, which is time-consuming and laborious.