SU339090A1 - Mixture for moulds and cores - Google Patents

Description

(54) MIXTURE FOR CASTING FORMS AND RODS

A known mixture for the manufacture of casting molds and cores, containing a filler — quartz sand, and a connecting mixture — an aqueous solution of a single-mixed aluminum phosphate and an additive that hardens the mixture — aluminum powder of zinc or iron.

In the invention for accelerating hardening; obtaining high strength and heat resistance, orthophosphorus {acidic acid in an amount of 1.5-5 wt. hours in combination with materials containing oxides of iron in the amount of 5-12 weight. h

As materials containing window. It has been proposed to use magnetite, hematite, ilmenite ores and chromium iron to. These materials are preferably used in the form of cone ore concentrates in fine grained metal.

The mixture has the following composition, parts:

Filler, for example

Powdery

aluminum0,2-0,6

Orthophosphoric acid 1,5-5,0

Water 0.5-2.0

If necessary, the proposed mixture can be transferred to a liquid state by adding 0.1 to 1.0 weight. including foam cutters from the class of surfactants.

In the proposed mixture, after 2-5 minutes after dispensing, a chemical reaction is indicated from the mixing preparation device, accompanied by an exothermic effect.

After about 3–10 min from the moment of the start of heat generation, the mixture sets and quickly hardens. Since the mixture has limited survivability, it is advisable to use common continuous mixers in foundry practice for the production conditions. The rate of hardening and the achievable strength of the mixture depends on the consumption of components, the concentration of orthophosphoric acid and the fineness of grinding as materials containing oxide.

of iron and the addition of an intensifier of hardening aluminum powder. Hardened rods and shapes do not require heat-drying and, having a high aapro content, can chill themselves with Metappos soon after HaroTOE.

Claims (2)

In the case of use as a material, its iron oxides, tsromomagnesite, the mixture is treated with the following properties. The compressive strength of standard samples after 15 minutes from the moment of preparing the mixture is 2.5 kg / cm, after 30 minutes 5.0 kg / cm, after 1 hour Yu kg / cm, after 24 hours 13 kg / cm. Gas permeability smv «« si after 1 h more than 2SO units Claim 1. Mixture for casting molds and stems | W {containing filler, addition of powdered aluminum and water, is distinguished by the fact that, with no self-curing in air, obtaining high-strength and heat resistance, it was introduced for it in combination with materials. containing iron oxides with the following ratio of components, parts by weight: Filler88-95 Materials containing 5-12 iron oxides Powdered and 0.2-0.6 aluminum Orthophosphoric acid 1,5-5,0 I O, 5-2, O Zod 2. A mixture of subsection 1, about one and two hours, with the fact that, as materials containing oxides of iron, in a mixture of BBOi is dite magnetite ore. For a mixture of claim 1, about t and u and y with the fact that the quality of the materials containing oxides of iron, in the composition of the mixture entered hematite ore. 4 / Mixture according to Claim 1, characterized in that, as the materials containing OKHCJtbi iron, lmenite ore is added to the mixture, 5, Mixture according to claims. 1 and 2, that is, that chromium iron was introduced into the mixture as materials containing iron oxides.