Magnesium alloy sawing knowledge

Magnesium and magnesium alloys can be cut by hand saw and power saw. Due to the small cutting force, the saw edge can be very deep. Therefore, the saw blade should have a large chip groove for flexible sawing. If the chip groove is too small, it will Quickly fill up the saw teeth to disengage the saw blade from the kerf. The outer edges of the teeth of the hand saw and hack saw must be on the same circumference. The serration relief angle should be large enough to minimize friction. Circular saw blades can be made of high-speed steel or inlaid with carbide teeth.

The tooth top of the magnesium alloy thick plate saw should be flat, and it can also have an inclination angle of 5° and have alternately arranged bevels. The peripheral speed limit of the high-speed steel circular saw blade is 610m/min, while the speed of the saw blade inlaid with carbide teeth can be as high as 3000m/min. The power of sawing magnesium alloy is about 1/10 of that of sawing mild steel. The saw blade with conventional structure diameter 305mm inlaid with cemented carbide teeth can cut 25mm thick plate at a speed of 86.4m/min.

Power hack saw is a common tool for sawing magnesium, the working speed can be as high as 160 strokes/min, and the feed rate is 0.38mm/stroke. The usual working speed of a power band saw is 365m/min.

Grinding

The grinding of magnesium alloys is not much work, because in most cases, the general cutting operation can obtain a bright surface. The surface roughness of the magnesium alloy workpiece processed with the diamond tip is 0.075μm~0.125μm, and the surface roughness of the standard tool is 0.25μm~0.75μm. If necessary, any grinding process can be used to process the magnesium alloy.

Alumina abrasive grains are often used for grinding magnesium alloys, and silicon carbide particles can also be used. Generally, more grinding results can be obtained with coarser particles. As with grinding most metals, the desired surface finish is achieved by controlling the feed rate, and the most commonly used grinding wheels are J or K hardness grades. Resin-bonded grinding wheels can be used for grinding magnesium alloy workpieces, but in most cases, vitrified-bonded grinding wheels are still appropriate. Dust will be generated during grinding, which is a kind of flammable and explosive dangerous goods. Safety regulations must be strictly followed, and no negligence should be made.