SUMITOMO AC8000P steel turning selection and troubleshooting

SUMITOMO AC8000P steel turning selection and troubleshooting

Steel turning is one of the most common processes in metal processing, but it is also the most prone to tool failure. From low carbon steel, high carbon steel to alloy steel, there are significant differences in hardness, toughness, and work hardening tendency among different materials. Engineers often face problems such as blade breakage, adhesion, crescent wear, back face wear, plastic deformation, and poor chip control. Faced with these faults, the AC8000P series coated hard alloy provides a complete solution from high-speed precision machining to heavy intermittent rough machining. This series includes four grades: AC8115P, AC8020P, AC8025P, and AC8035P, which are respectively designed for high-speed continuous processing, high-efficiency intermittent processing, universal processing, and heavy intermittent processing. This article will provide a systematic troubleshooting and selection guide from five dimensions: brand positioning, coating technology, chip breaker selection, recommended cutting parameters, and practical cases.

Brand positioning and troubleshooting logic

The core idea of the AC8000P series is to match different cutting conditions and failure modes through differentiated combinations of coating technology and substrate materials. Engineers can quickly identify suitable grades based on specific issues that arise during processing.

AC8115P: High speed continuous machining and resistance to plastic deformation

AC8115P is the preferred grade for high-speed machining, with a wear resistance of 1.5 times that of conventional tools and a plastic deformation resistance of over 2 times. When there is rapid wear of the back cutting surface, plastic deformation of the cutting edge, coating peeling or severe crescent wear during processing, AC8115P is the preferred choice. It is suitable for high-speed continuous turning, dry cutting, and precision machining of high hardness materials. The recommended chip breakers are EFE, ESE, and ESU, where EFE is used for small depth precision machining, ESE is used for efficient precision machining, and ESU is used for general precision machining.

AC8020P: Efficient Processing and Anti chipping Blade

AC8020P is positioned as an efficient processing grade, with anti chipping performance that is more than 2.5 times that of conventional tools. When cutting edge breakage, boundary defects, or damage caused by impact loads occur during processing, AC8020P can provide excellent stability. It is suitable for forging, intermittent cutting, and working conditions that require an increase in feed rate or cutting speed. Recommend EGE and EGU for chip breaking grooves. EGE is suitable for increasing feed rate, while EGU is suitable for increasing cutting speed.

AC8025P: Universal Processing and Anti Adhesion

AC8025P is the preferred recommended grade for general processing, with anti adhesion and anti chipping performance more than twice that of conventional tools. When chip adhesion, chip accumulation, surface quality deterioration, or slight chipping occur during processing, the surface smoothing treatment of AC8025P can significantly suppress adhesion and the resulting chipping. It is suitable for a wide range of working conditions from precision machining to rough machining, from continuous cutting to light intermittent cutting. The recommended chip breaker is EGU, which can also be paired with EFE, ESE, ESU, EGE, EUX, EME, EMU, EMX, etc.

AC8035P: Heavy intermittent machining and fracture resistance

AC8035P is positioned as an intermittent processing grade, with fracture resistance performance more than twice that of conventional tools. Its special surface treatment reduces the residual tensile stress in the coating, significantly suppressing crack propagation and fracture. When severe blade breakage, hot cracking, rapid fracture, or heavy intermittent impact damage occurs during processing, AC8035P is the preferred solution. It is suitable for heavy intermittent turning, unstable working conditions, and rough machining of high hardness materials. Recommended chip breakers are EGU and EUX. EGU is used to extend tool life, while EUX is used for stable cutting.

Analysis of Coating Technology

The reason why the AC8000P series can maintain stability under different working conditions lies in the collaborative design of coating technology and substrate materials.

Coating architecture of AC8115P

AC8115P adopts a four layer key design. The first layer is a hard surface layer that reduces initial wear while providing high compressive stress and a golden appearance, making it easy to identify the used blade tip angle. The second layer is a crystal orientation controlled ultrafine alumina layer, which improves the coating strength by controlling the crystal growth direction, suppresses wear caused by crystal detachment, and achieves wear resistance of more than 1.5 times that of conventional tools. The third layer is a high hardness fine-grained TiCN layer, which significantly improves the hardness of the coating through a fine and uniform crystal structure. The fourth layer is a newly developed hard alloy matrix that is resistant to plastic deformation. By improving its high-temperature performance, its ability to resist plastic deformation is more than doubled. In the external turning of 4137 steel, the wear of the rear cutting surface of AC8115P at 8 minutes is only 0.006 inches, while that of competitor A is 0.008 inches; In the dry cutting of W1-8 tool steel, conventional tools experience wear on the back cutting surface within 2 minutes due to plastic deformation, and even coating peeling occurs on competitor B, while AC8115P can continue processing after 4 minutes.