How Mitsubishi’s MC6100 Turning Inserts Tame Tricky Steel-Machining Jobs

You know you’ve built a good machining tool when workers start hiding it from acquisitive colleagues as soon as their shifts are over.

That’s what happened when Mitsubishi Materials, a maker of machining equipment, gave some samples of its 6100-series steel-turning inserts to participants in a turning class, says Brian Jewell, technical support and training specialist with Mitsubishi.

“They said that understanding how the chip-breakers matched up to the grades and being able to apply them correctly had really increased their productivity to the point that they were putting them back in their toolboxes at the end of each shift, then bringing them out the next day and running them again,” he adds.

Launched in 2020, the 6100 series is the second generation of turning grades for ISO-P workpiece materials, a category that includes steel and steel alloys and can be tricky to machine because of variations in heat resistance, abrasiveness and adhesion that are more consistent in other letter-designated metal groups.

“For example, a sharp-edged tool engineered to counter the adhesion tendencies of a low-alloy steel may not be able to withstand the abrasive characteristics of another steel composition,” an article in Metalworking World Magazine explains. “In addition, development of specialized steel alloys continues unabated as manufacturers seek materials matched to the particular performance demands of their customers’ parts.”

Variants in Mitsubishi’s 6100 series include the 6115 for high-speed turning, the 6125 that offers stable tool life over a wider range of machining applications and the more recent 6135, engineered for fracture resistance.

The last two digits in the insert’s name indicate the amount of interruption due to factors such as resistance and pinch points that the tool can handle, a quality that increases as the numbers rise, Jewell says.

Increasing Wear Resistance

The MC6135, introduced in October, is built with what Mitsubishi calls super nano texture technology that enables thicker coatings of aluminum oxide for heat resistance than conventional chemical vapor deposition techniques, in which grain size and growth direction are uneven.