Austempered ductile iron is a new type of wear-resistant alloy cast iron. It has a high hardness of HRC45-55
after austempering and has high strength. It is extremely hard to wear with ordinary hard alloy inserts, and
its machining efficiency is low.
In the past, there was no excellent cutting method for this new type of alloy cast iron, which limited the
production of austempered ductile iron for mass production. After research and experiments have proved
that CBN inserts have a good effect on the processing of austempered ductile iron.
CBN inserts have been proved to be suitable for nickel hard cast iron processing.
Austempered ductile iron processing tool test:
Workpiece: Austempered cast iron liner
Tool: CBN inserts and carbide inserts
Parameters: CBN inserts cutting parameters: the rough machining speed is 90 m/min, the unilateral machining
allowance is about 1mm, the feeding amount per revolution is 0.4mm, the finishing unilateral allowance is 0.3mm,
and the linear speed is 150m/min. Feed rate 0.2mm.
Carbide inserts cutting parameters: linear speed 30 m/min, machining allowance and feed rate are the same as
above, and the tool wear is severe and finally leads to chipping.
Tool life comparison: CBN tools are 7 times that of carbide tools. Processing efficiency increased by 3 times.
- For the austempered ductile iron finishing, if the unilateral allowance is about 0.2mm, ceramic inserts
can also be considered to comprehensively compare the economy of the selected tool; if the machining
allowance exceeds 0.3mm, using pcbn inserts is better.
- After the CBN inserts for finishing, and then used for rough machining, which can greatly reduce the tool cost.