Matters needing attention in the machining of glass fiber reinforced plastic

2022-05-18 22:06:48

We all know that metal materials can be processed by turning, pliers, planing, milling, etc., but composite materials? If possible, that would greatly improve the fineness of the workpiece. Fang Zhen tells you that FRP material can also be machined. In addition to welding, which cannot be satisfied by non-metallic materials, machining such as turning, milling, planing, grinding (sawing), drilling, riveting, and reaming can be satisfied. The material machining method is basically the same, and different machining is required to meet the complex shape and surface smoothness of the product.

FRP is a thermal insulator and is hard and brittle, with high mechanical strength and poor thermal conductivity. Deformation, severe wear of the blade, easy damage to the quality of the machined surface, splitting, delamination, fluffing and other defects. Therefore, in the cutting process, the tool wears quickly, the workpiece is easy to layer, slag, and fall off, and the dust is serious. Therefore, a reasonable tool material must be selected during turning, the cutting ability of the tool must be exerted, and the cutting conditions must be controlled so that it will not be scorched. Therefore, FRP machining can be said to be a special machining process and a special process method.

Under possible conditions, it is best to use synthetic polycrystalline diamond or cubic boron nitride composite cutting tools, which not only greatly improves the cutting speed, but also improves the tool durability by dozens of times more than cemented carbide. Because glass fiber reinforced plastics are mostly brittle materials, its elastic modulus is small, and its elastic recovery is large.

FRP material machining precautions:

(1) Because the mechanical properties of FRP material are brittle materials, it is fragile, so it is difficult to hold. If the clamping force is too large, the workpiece will be deformed, or the workpiece will be damaged. If the clamping force is too small, the workpiece will fly off.

(2) Due to the poor heat dissipation of glass fiber products, the linear expansion is relatively large, the workpiece is easily deformed, and the size is difficult to control.

(3) FRP powder is irritating to human skin. Attention should be paid to dust prevention to protect the personal safety of workers.

(4) In order to prevent the phenomenon of layering and slag dropping at the cut-in and cut-out, on the one hand, the feed rate is reduced at the cut-in and cut-out place, and on the other hand, the turning tool is used to turn it into a 45-degree angle at the cut-in and cut-out place; the turning tool for threading , a larger rake angle of -10° to -15° should be used to ensure the integrity of the tooth shape.