Method and device for vacuum magnetron sputtering of aluminized film on hub of automobile

Abstract

The invention discloses a method for vacuum magnetron sputtering of an aluminized film on a hub of an automobile, which is characterized in that: the sputtering voltage is more than or equal to 1,200V and the sputtering current is more than or equal to 110A. The adopted device comprises a vacuum chamber; a plurality of vertical crankshaft type autorotating hanging rods which are used for hanging workpieces and revolute around the vertical central axis of the vacuum chamber are arranged in the vacuum chamber; the autorotating hanging rods comprise autorotating main shafts, crank arms and crankarm shaft components, which are fixedly connected to form crankshaft shapes; the crank arm shaft components are provided with hub fixtures; and the hub fixtures clamp hubs to ensure that the middle points of horizontal hub axes are positioned on autorotating axes of the autorotating hanging rods. The device comprises a driving mechanism for driving the crankshaft type autorotating hanging rods tohang and clamp the hubs, revolute around the axis of the vacuum chamber and autorotate, and driving the hubs to autorotate around the axes of the hubs. By the invention, large-size hubs with complicated shapes can be uniformly plated with aluminized films. The invention has the advantages of no environmental pollution, uniform film coating, high yield and low cost.

Description

technical field [0001] The invention relates to a method for vacuum aluminum coating, in particular to a method for vacuum magnetron sputtering aluminum coating on automobile wheel hubs. The invention also relates to a device for implementing the above method. Background technique [0002] In the 1990s, aluminum alloy wheels for cars came out. Aluminum alloy wheels are light in weight and energy-saving. At the same time, aluminum has good thermal conductivity, and the wheels are close to the brake drum, which is conducive to heat dissipation. Therefore, aluminum alloy wheels soon replaced steel wheels. However, it is difficult to polish aluminum alloy into a bright mirror surface. Cu / / Ni / / Cr coating is usually electroplated by water method in order to obtain a bright Cr surface and enhance the aesthetic feeling. This traditional process used to be popular for a while, but there are serious deficiencies in this process: first, the water electroplating process has great env...

AI Technical Summary

Problems solved by technology

This traditional process used to be popular for a while, but there are serious deficiencies in this process: first, the water electroplating process has great environmental pollution; second, the water electroplating process mostly uses Ni as the transition layer, and Ni is expensive Second, Ni is also restricted by environmental protection and is not popular; third, when large-scale water electroplating is used, because the chrome plating tank is easily polluted by impurities, the chrome plating layer is prone to defects such as pitting, the yield is low, and the defective rate reaches 20%. high cost

[0003] Finally, there is the problem of the uniformity of the magnetron sputtering coating on large-sized coating parts such as the hub. If the usual straight rotation hanging rod and the movement mode of the hub and the rotation of the hanging rod are used in the vertical vacuum chamber, uniform coating cannot be achieved. of

Because the hub is clamped on the side of the straight rotation hanging rod, when the large diameter of 500mm faces the sputtering target surface, the depth direction of the hub reaches more than 250mm, which is far beyond the normal uniform aluminum coating distance of the sputtering target (100-150mm) ), there must be chromatic aberration along the depth direction, the aluminum film near the target is white and bright, and the aluminum film at the far target is slightly dark. the result of

[0004] In addition, in addition to the large size, the shape of the automobile wheel hub is relatively complex. In particular, there is little space between the adjacent ribs at the denser ribs of the hub. The rest of the aluminum plasma passes through the narrow space between the spokes and reaches the rear part of the ribs for deposition, which has an "indirect shielding" effect on the front and back. If the commonly used magnetron sputtering process parameters are used for aluminum plating, aluminum plasma often The volume will be insufficient, and there will still be a large color difference, that is, the aluminum coating near the target surface is bright white, and the coating on the far target surface where the hub ribs are denser is gray and dark

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