摘要:
A method for controlling the dewaxing of a ceramic investment casting shell assembly is provided whereby the shells are immersed in a fluid having a relatively low boiling point, e.g., below about 230F. The fluid must be hot enough to transfer heat though the shell assembly so as to melt the wax pattern, but low enough so as to limit steam generation as a result of moisture in the shell. By controlling the rate of immersion of the shell in the hot fluid bath, shell cracking can be greatly reduced.
摘要:
A moulding material for casting iron contains sand and a carbonaceous material, the carbonaceous material comprising pit coal. The main component of the carbonaceous material, relatively to each of the components of the carbonaceous material, is coke. Also provided is a use of such a moulding material, a method for casting iron and an additive for the moulding material.
摘要:
A composition which comprises a soluble or partially soluble phosphate, a refractory material and less than 1% of an oxide or hydroxide of magnesium or calcium. The composition may be mixed with water to form an investment casting slurry into which a wax pattern may be dipped. Slurry coated onto the pattern may be set by applying a stucco composition which comprises an oxide or hydroxide of magnesium or calcium. Coats of set slurry may be built up on the pattern to form an investment casting shell.
摘要:
An object is to propose a mold release agent improving the state of a mold surface by repeating casting cycle so as to extend the life of the metal mold actively, and a casting method using the mold release agent. A water-soluble mold release agent applied on a mold surface of a metal mold contains organic acid or organic acid salt which is reducing and ligand, wherein concentration of a total thereof is not less than 0.01wt% in using concentration and is not more than a fixed concentration which is stability limit of emulsion of the mold release agent in undiluted concentration. Construction weight ratio of the organic acid or organic acid salt which is reducing and the ligand is in the range from 99/1 to 30/70. The mold release agent is applied on a mold surface of a die casting metal mold, molten metal is injected into the metal mold, and the organic acid or organic acid salt which is reducing in the mold release agent is reacted with a component of the mold surface so as to deoxidize Fe2O3 on the mold surface to Fe3O4.
摘要:
A parting compound for green sand molding, which contains hydrocarbon oil as the principal agent and other essential components including a surfactant as a dispersant and an anionic surfactant and/or strongly basic amine as a wettability improver. This compound is used in the form of oil-in-water emulsion by diluting with water. Because of the dilutability with water, this compound can be readily stored and transported in a nonbulky state. Furthermore, the proportion of water can be increased as compared with that of the hydrocarbon oil in the step of applying the compound, thus contributing to resource saving and improvement in the resistance to fire hazard.