MMC Magazine

How much could we smoothen the surface?

– Would you please give us a little background on the development of the UC51 series?

Hara: The UC51 series was launched in 2005. Similar products by different manufacturers whose cutting surface was smoothened (in black) had a known market share. To exceed that share, we needed to offer performance that was significantly better. We considered smoothening the entire surface of the insert because it was obvious that focusing on the cutting face alone would not maximize performance.

Nishida: Our competitors also realized that at the time. However, improvements in the smoothening process would increase insert production efficiency and allow the identification of worn corners. Considering production costs and ease of use as well as performance, however, they may have hesitated to focus on the entire surface.

Honma: Significant extension of tool life can be achieved through the improvement of both wear and chipping resistance. The key to achieving both was the integration of surface and coating technologies. We examined a wide range of approaches for surface processing before deciding upon the wet-blasting method. We were lucky to have a wet-blasting device on hand. We could readily verify a wide range of factors and this helped us during the different phases, something that led to a significant breakthrough.

Hara: Removing the gold coating on the surface of the inserts completely to make them all black meant sacrificing the ability to identify worn corners. At the beginning of development, the majority of our sales staff was against the idea and this made it difficult to move forward with development.

Nishida: Indeed, identifying worn corners is very important. However, I believed that offering outstanding performance could help our customers more. When we realized that the establishment of new surface processing and coating technologies would enhance performance more than expected, the negative opinions about an all-black insert gradually subsided.

Honma: When we received feedback from pre-sales field testing, we felt that our decision had been justified. Our customers reported that it was a challenge to identify worn corners but as compensation, they were very satisfied with the cutting performance.

Hara: Domestic tests showed a three-fold improvement in performance over existing products. We sought and achieved the best performance in the industry, and this gave us confidence to initiate sales of the all-black super-even coating.

– What challenges did you encounter during development?

Honma: When we were discussing ideas at the beginning of development, my supervisor asked me to produce mellow, springy materials. I remember clearly wondering what he was talking about.

Hara: Yes, we all wondered what was up. We were discussing a cutting tool, but we were asked to think of the development in something of a mellow and springy way rather than a hard task.

Nishida: But, when we checked the quality and texture of the tool, it is indeed metaphorically mellow and springy in comparison with other grades, or, technically speaking it is durable and versatile.

Outstanding performance gained tremendous popularity

– Did you expect this grade to be such a big hit?

Hara: We were certainly confident about the quality, but we didn’t expect that it would be so popular.

Nishida: Tool sales were supported by the rapidly growing Chinese cast iron machining market. Word-of-mouth is a major factor in the Chinese market; and once a customer takes to a product, its good reputation spreads quickly.

Honma: Since we only had one wet-blasting device, it was impossible to keep up with demand. Of course, we wanted to increase production to meet demand, but we were also quite pleased with what we had achieved.

Nishida: The key to success was having surface-processing technology based on the wet-blasting method, and having coating technology capable of enhancing that surface-processing technology to the maximum extent. It was a big surprise to see that the integration of two different technologies could bring such a significant achievement. That experience was extremely valuable for me.

– Following this, the MC50 series was launched as the replacement for the UC50 series.

Nishida: Of course our competitors' progress was a significant factor in the development of the MC50 series, but we also wanted to develop tools for ductile cast iron, which has higher hardness than standard cast iron, and we wanted to offer cemented carbide CVD coated inserts for customers that machine cast iron using ceramic inserts.

Honma: The performance of the MC50 series for machining FCD700 is exceptional.

Nishida: MC5015’s middle-layer coating has been improved significantly to maintain performance during interrupted cutting and tool life is 2 to 3 times higher than the existing product. We also applied our patented TOUGH-Grip technology (toughening technology for coating) to the MC50 series for the first time.

– Do you have anything you’d like to say to our readers?

Hara: When I joined the UC51 series development team, it was only my second year at Mitsubishi Materials. While we had to work on a wide range of properties, we maintained our focus on performance. I would like to tell young developers not to give up. That’s the ticket to success.

Nishida: As a developer, it is necessary to discover the rules and principles for each phenomenon. If we understand these, we can apply them to the development of subsequent products.

Hara: Analysis at that time was at the micron level while it’s now on a Nano scale. Enthusiasm is important in the drive for top performance in the industry and a cool head is required for logical analysis.

Nishida: We developed this tool with a focus on cutting performance. From the viewpoint of ease of use, we considered the corner identification function as an important performance metric. From now, we will develop products not only with a focus on cutting performance, but also ease of use.

Honma: We would like to expand the surface processing technology we have accumulated through development of the UC51 series and apply it to applications over a wide range of products.