1. Types and processing characteristics of cast iron
Cast iron can be classified into gray cast iron, white cast iron, malleable cast iron, ductile cast iron, vermicular cast iron, alloy cast iron, etc. Among them, gray cast iron is widely used in the automotive industry, and the automotive industry is a major demander of CNC tools, so processing plants often have gray cast iron processing needs.
2. What tools are used to process ordinary cast iron
The common ordinary cast iron referred to in this article is gray cast iron, ductile cast iron and austenitic cast iron. Gray cast iron has good processing performance. For example, alumina-coated carbide milling cutters can generally be used for gray cast iron cutting. Ductile iron has its processing performance affected by its graphite content. Generally, it can be processed with an integral carbide bar economical coated alloy milling cutter.
For ordinary cast iron processing tools, economical tungsten steel milling cutters can be competent. Secondly, cobalt-containing high-speed steel tools can be used.
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3. What kind of tools are used for difficult-to-process cast iron
Here we will only take chilled cast iron as an example. Chilled cast iron is a kind of wear-resistant cast iron. It is formed by accelerating the cooling of the surface of the cast iron part during casting, so that its surface obtains the cast iron structure, forming the characteristics of high hardness and high wear resistance. Chilled cast iron can be divided into ordinary chilled cast iron, nickel-chromium chilled cast iron, high-chromium white cast iron and chrome-vanadium white cast iron.
1) Processing characteristics of chilled cast iron
Chilled cast iron has high hardness, great brittleness, and high unit cutting force. Moreover, its chips are in a broken shape. Because the contact between the tool tip and the cutting is very short, the cutting force and cutting heat are concentrated near the cutting edge, which easily causes the tool to wear and damage. Most of the workpieces processed by chilled cast iron are blanks, and the machining allowance is large and uneven, which increases the difficulty of cast iron machining. Of course, there are good solutions for cast iron machining tools and cast iron milling cutters.
2) Selection of tools for machining cold cast iron
It is best to choose tool materials with high hardness, good wear resistance and certain strength for machining cold cast iron. Generally, fine-grained or ultra-fine-grained YG-type cemented carbide or alumina ceramic tools with coating are used.
3) Cutting amount of milling cutter for machining cold cast iron
Carbide tools; low speed and large feed. V=9m/min or so, the feed rate is generally selected according to the main deflection angle and the back cutting amount. 0.5mm/r is selected for rough machining of cast iron, and 0.1~0.4mm/r is selected for fine machining of cast iron.
Ceramic tools; generally choose high-speed milling, V=50~80m/min for rough and semi-finishing of cast iron, and V=80~120m/min for fine machining.
Cast iron machining tools, such as knife grains, can be rough, semi-finished and finely machined. If you still don't know what milling cutter to use for cast iron, of course, YG-type carbide tools are selected for machining cast iron milling cutters.
