SUMITOMO AC6000M Stainless Steel Turning Guide

SUMITOMO AC6000M Stainless Steel Turning Guide

Stainless steel turning has always been a challenging step in metal processing. Whether it is austenitic, martensitic, ferritic, or duplex stainless steel, problems such as adhesion, chipping, crescent wear, flank wear, work hardening, and poor chip control may occur during the machining process. Faced with these faults, engineers often need to make a trade-off between wear resistance and resistance to chipping. The AC6000M series coated hard alloy is a complete product line designed to solve this contradiction, including four grades: AC6020M, AC6030M, AC6135M, and AC6145M, covering precision machining, continuous machining, light intermittent machining, and heavy intermittent machining, respectively. 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 AC6000M series is to match different cutting conditions and fault modes through a differentiated combination of CVD and PVD coating technologies.

AC6020M: The preferred choice for precision machining and high-speed machining

AC6020M adopts a combination of CVD coating and high hardness hard alloy substrate, providing stable and long tool life in precision machining and high-speed machining. When problems such as rapid wear of the rear cutting edge, insufficient sharpness of the cutting edge, and decreased surface quality occur during processing, AC6020M is the preferred choice. It is suitable for continuous cutting and light intermittent cutting, especially in precision machining of ferritic stainless steel, martensitic stainless steel, and precipitation hardened stainless steel. The recommended chip breakers are EEF and ESU, with EEF emphasizing chip control and ESU emphasizing suppression of cutting forces.

AC6030M: Preferred recommendation for continuous cutting

AC6030M is the preferred recommended grade for continuous cutting, and its CVD coating significantly reduces common abnormal damage in stainless steel processing, achieving long-term stable tool life. When the machining condition is continuous turning and the main faults are crescent wear, wear on the back cutting surface, or surface quality deterioration caused by adhesion, AC6030M is the best choice. It is suitable for continuous processing of ferritic, martensitic, austenitic, and precipitation hardened stainless steels. EGU and EEG are recommended for chip breaking grooves, with EGU being the universal preferred option and EEG emphasizing chip breaking control.

AC6135M: A New Choice for Light Intermittent and Black Leather Processing

AC6135M adopts a new PVD coating, which balances wear resistance and chipping resistance in light intermittent processing and black skin processing. When unstable cutting occurs due to slight chipping, boundary defects, or black skin during processing, AC6135M can provide more stable performance. It is particularly suitable for light intermittent processing of austenitic stainless steel and duplex stainless steel. Recommend EGU and EEH for chip breaking grooves, with EGU being the universal preferred option and EEH used for stable intermittent turning.

AC6145M: A powerful tool for heavy intermittent processing

AC6145M adopts a combination of PVD coating and high toughness hard alloy substrate, which performs excellently in heavy intermittent processing. When severe chipping, rapid fracture, hot cracking, or cutting edge impact damage occurs during processing, AC6145M is the preferred solution. It is suitable for heavy intermittent cutting and unstable working conditions, especially for rough machining of austenitic stainless steel and duplex stainless steel. The recommended chip breaking grooves are EEH and EEM. EEH is used for stable heavy intermittent turning, while EEM is used to suppress rapid fracture.

Analysis of Coating Technology

The reason why the AC6000M series can maintain stability under different working conditions lies in the differentiated design of coating technology.

CVD coating architecture of AC6020M and AC6030M

AC6020M and AC6030M adopt CVD coating technology, and their coating structure includes four key design layers. The first layer is a surface smoothing treatment layer, which significantly suppresses adhesion and the resulting chipping by improving anti adhesion performance. The second layer is a high toughness aluminum oxide layer, providing stable and long tool life. 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 high adhesion technology, which significantly improves the adhesion strength through a smooth coating and substrate interface. This coating combination enables AC6020M and AC6030M to effectively resist crescent wear and flank wear in continuous cutting and high-speed machining.

PVD coating architecture for AC6135M and AC6145M

AC6135M and AC6145M use TiAlBCN based multilayer coatings, providing higher wear resistance, anti chipping and anti adhesion properties. Its coating structure also includes four key design layers. The first layer is an anti adhesion layer, which uses TiCN based components with excellent lubricity to suppress adhesion and the resulting chipping. The second layer is a wear-resistant layer, which uses a proprietary high hardness TiAlN based multi-layer coating to significantly suppress crescent wear and rear blade wear. The third layer is the anti chipping layer, which uses ultrafine grained TiAlN based components with excellent toughness to suppress accidental chipping. The fourth layer is high adhesion technology, which enhances the adhesion strength of the coating and improves stability through special techniques. This coating combination enables AC6135M and AC6145M to effectively absorb impact energy during intermittent cutting and heavy intermittent machining, suppressing chipping and hot cracking.