Three Common Mold Repair Methods

- Sep 06, 2018-

Mold is an important tool for manufacturing products. The quality of the products will directly affect the quality of the products produced, in order to prevent the mold from falling, deforming, wearing, and even breaking. We need to do a good job of predicting the mold repair method. There are many mold repair methods, but there are three common types: argon arc welding repair, brush plating repair and laser overlay welding repair.


1. Argon arc welding repair


The arc that is burned between the continuously fed wire and the workpiece is used as a heat source, and the gas ejected from the torch nozzle protects the arc for welding. At present, argon arc welding is a commonly used method and can be applied to most major metals, including carbon steel and alloy steel. MIG welding is suitable for stainless steel, aluminum, magnesium, copper, titanium, zirconium and nickel alloys. Due to its low price, it is widely used in mold repair welding, but the welding heat has large area and large solder joints. Precision mold repair has been gradually replaced by laser welding.


2. Brush plating repair


The brush plating technology uses a special DC power supply device. The positive electrode of the power supply is connected with a pen as the anode during brush plating. The negative electrode of the power supply is connected to the workpiece as the cathode during brush plating. The plated pen is usually made of high-purity fine graphite block. Anode material, the graphite block is covered with cotton and wear-resistant polyester cotton sleeve.


During operation, the power supply component is adjusted to a suitable voltage, and the pen that penetrates the plating solution moves back and forth on the surface of the workpiece to be repaired at a relative relative speed, and maintains a certain pressure until a uniform ideal metal deposition layer is formed. Due to the contact between the plated pen and the surface of the workpiece being repaired, the metal ions in the plating solution diffuse to the surface of the workpiece under the action of the electric field force, and electrons are reduced to metal atoms on the surface, so that the metal atoms are deposited and crystallized to form a plating layer. That is, the desired uniform deposition layer is obtained on the face of the repaired plastic mold cavity.


3. Laser surfacing repair


Laser welding is a welding of a laser beam that is focused by a high-power coherent monochromatic photon stream. This welding method usually has continuous power laser welding and pulse power laser welding. The advantage of laser welding is that it does not need to be carried out in a vacuum. The disadvantage is that the penetration force is not as strong as that of electron beam welding. Accurate energy control during laser welding enables precision soldering of devices. It can be applied to many metals, especially to weld some difficult-to-weld metals and dissimilar metals. It has been widely used in the repair of molds.