Precision vacuum-casting method for foaming-mould aluminum casting

Abstract

The invention discloses a precision vacuum-casting method for foaming-mould aluminum castings, which comprises the following steps of: placing models, covering a film, arranging a casting-head rod and a steam-discharging pipe, molding an upper box, demoulding, repairing, molding a bottom box, closing the boxes and matching the models, casting and the like. Multiple defects in the aspects of foaming-mould aluminum casting are radically solved according to the invention, so that the increasingly-perfect process effect of a casting product is achieved, and design standards can be reached without accurately machining the castings. The precision vacuum-casting method has the advantages of simple process, easiness in operation and strong applicability; and compared with the traditional vacuum-casting method, more than 20 percent of molten aluminum can also be saved, and the precision vacuum-casting method is economical and practical.

Description

technical field [0001] The invention relates to a precision casting method for solving the casting defects of EPS, EPP, PU and other foam mold aluminum castings, and is a precision vacuum casting method for foam mold aluminum castings. Background technique [0002] EPS, EPP, PU and other foaming molds are widely used in the manufacture of molding products such as packaging, building materials and automotive interior parts, and most of them are cast with aluminum alloy. Aluminum alloy has the advantages of light weight, moderate hardness, easy processing, low cost, strong thermal conductivity and corrosion resistance, and has always been the material of choice for foam mold castings. [0003] However, since foaming molds such as EPS, EPP, and PU are hot molds, foaming molds must have good thermal conductivity and corrosion resistance in terms of energy saving, durability, and improvement of mold production efficiency. And the characteristics of long-term stress caused by the...

AI Technical Summary

Problems solved by technology

[0004] The melting point of aluminum alloy is between 680°C and 720°C. It is low-temperature casting, with little room for temperature control, poor fluidity of aluminum solution, and prone to dissatisfaction in cavity pouring; inaccurate control of vacuum degree, prone to cavity collapse; Foam molds have different shapes, large volumes, and uneven wall thicknesses. The aluminum solution is often not fully in place during pouring, and improper feeding makes it difficult to guarantee the dimensional accuracy of the castings. The surface crystallization state of aluminum mold castings is different from that of the core, and the internal stress is large. Cracks are prone to occur, increasing the thickness will reduce the thermal efficiency and waste energy; the aluminum liquid has strong air absorption, the casting has many pores, and the surface finish is not ideal

[0005] The general vacuum casting method fails to solve the above foam mold aluminum casting defects