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1. Low cutting force, poor thermal conductivity and heat resistance: the cutting force in CNC machining of engineering plastics is 6-7 times smaller than that of metal, but the cutting speed is correspondingly reduced due to low thermal conductivity and heat resistance, so as to prevent plastic softening and tool sticking;

2. Uneven structure and strength: plastic is composed of many components, and there are many ways to express the components, resulting in uneven structure, which is not conducive to processing, so the cutting edge of the tool should be sharper and more wear-resistant during cutting;

3. The cutting tools are severely worn and prone to brittle cracking: engineering plastics add more fillers and additives, especially glass fiber, which will be difficult to cut. The cutting tools will be worn quickly. After the cutting tools are blunt and the extrusion pressure is high, cracks and edge collapse will occur;

4. Large thermal expansion coefficient: the expansion coefficient of plastic is 3-4 times that of metal, which affects the dimensional stability and brings difficulties to machining;

5. Difficult chip breaking: during turning and drilling, the chips are banded, which will wrap around the tool and squeeze each other, affecting the processing quality.

This article is from Jiangmen Engineering Plastics:http://www.hhaifeng88.cn/