CBN Inserts & Automotive Engine Blocks: High-speed Machining Technology Exploration

The machining accuracy of automotive engine cylinder blocks determines the overall performance of the engine.  Challenges such as wear from hard points in gray cast iron and deformation of thin-walled aluminum alloy components place stringent demands on cutting tools. Traditional cutting tools suffer from short lifespan and low efficiency, while imported CBN tools are expensive, hindering production line operation.

SCBN TOOLS CBN inserts overcome these challenges with three core advantages: ultra-hard and wear-resistant, with a hardness of HV4200 and wear resistance 12 times that of coated cemented carbide, allowing a single insert to machine over 1000 gray cast iron cylinder blocks; high-temperature stability, withstanding temperatures up to 1300℃, suitable for high-speed cutting at 800-1800 m/min, reducing workpiece thermal deformation; and customized design, with specialized inserts covering all processes including milling and boring, improving chipping resistance by 60% and preventing deformation during the machining of thin-walled parts.

For the cast iron parts of the engine, SCBN TOOLS commonly uses round inserts RNGN0903 and RNGN1203, available in two types: solid CBN and full-face CBN, offering larger cutting depth, better wear resistance, and impact resistance; for aluminum alloy parts, round PCD full-face inserts RNGN0903 and RNGN1203 are commonly used to ensure the required surface accuracy of the workpiece; for steel parts, we select different materials and grades for our customers depending on the processing area to suit both continuous and intermittent machining conditions.

A leading domestic automotive manufacturer has applied SCBN TOOLS CBN inserts to its diesel engine gray cast iron cylinder block production line.  With optimized cutting parameters of Vc=1000m/min and fr=0.12mm/r, tool life was extended by 20% compared to imported brands, resulting in a 25% reduction in overall processing costs. In the machining of aluminum alloy cylinder blocks for new energy vehicles, these inserts achieved continuous processing of 600 pieces without wear, with a 100% pass rate for cylinder bore dimensional consistency, helping the company successfully achieve its production capacity ramp-up targets.