Centrifugal casting method for asymmetric annular high-lead bronze casting

Abstract

The invention provides a centrifugal casting method for an asymmetric annular high-lead bronze casting, and belongs to the field of casting technology. The method includes the following steps that (1) Alloy material for casting is smelted to from alloy melt; (2) a casting mold is made, the casting allowance of the outer surface and the lower surface is set as 3 mm to 6 mm of a single face, and the casting allowance of the upper surface is 5 mm to 10 mm of a single face; (3) coating is conducted through coating; (4) the casting mold is fixed to an centrifugal casting machine, the centrifugal casting machine is started, and under the condition that the casting mold rotates, the alloy melt is casted into the casting mold; (5) the alloy melt is cooled to normal temperature. By means of the centrifugal casting method for the asymmetric annular high-lead bronze casting, the segregation problem of high-lead bronze alloy is solved, mechanical performance of the product and precision of the casting are good, and near-net shaping is achieved.

Description

technical field [0001] The invention belongs to the technical field of casting, and particularly relates to a centrifugal casting method for an asymmetric annular high-lead bronze casting. Background technique [0002] Lead bronze is a lead-containing copper alloy, which has been widely used in the machinery manufacturing industry in the early 20th century, mainly used in the manufacture of aero-engines, heavy oil engines and other bearings that work at high speed and high pressure; its working performance far exceeds that of babbitt and Other copper alloys. [0003] The lead in lead bronze is not completely dissolved in the alloy, and the independent tiny particles are evenly distributed in the copper matrix, so it has an excellent function of maintaining lubricating oil and reducing friction coefficient; the friction coefficient of lead bronze is 0.004~0.008 (with lubrication), 1~4 times lower than other copper alloys; lead bronze bearings can work under surface pressure ...

AI Technical Summary

Problems solved by technology

[0005] Usually high-lead bronze sleeves are produced by casting methods, but there are many technical difficulties in casting due to the large difference in the melting points of copper and lead and the solidification characteristics of the alloy itself; from the Cu-Pb alloy phase diagram, it can be seen that high-lead bronze alloys, in the liquid state Although a single uniform liquid phase can be formed, there is copper below the liquidus line. a The primary crystal precipitates, and a monotectic reaction occurs near 950°C; in the solid state, because lead is insoluble in copper, lead is distributed in the copper matrix as an independent phase, so regional segregation is easy to occur, and at the same time due to the density of lead It is 11.34, which is much higher than the density of copper, which is 8.93, so it is prone to specific gravity segregation, which brings great difficulties to the casting of high-lead bronze.

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