Choose a Turning Insert Grade by Workpiece Material

Choosing turning insert grades by material begins with the drawing and stock specification. A shop description such as “stainless” or “aluminium” is useful conversation, but it is not a complete purchasing specification. This guide is a practical worksheet for narrowing the options with a toolmaker.

Turning insert grades by material family

The ISO application groups are P for steels, M for austenitic and duplex stainless steels, K for cast irons, N for nonferrous materials, S for heat-resistant alloys and titanium, and H for hardened materials. Some ferritic and martensitic stainless steels fall within P. Confirm the subgroup rather than treating every stainless alloy as M.

Record what is on the job

Copy the exact alloy designation, stock condition and specified hardness into your setup sheet. Include any heat-treatment information supplied with the job. If that information is missing, ask the stock supplier or engineering contact before building a recommendation around a guessed material.

Next, describe the cut in plain terms: continuous outside turning, an interrupted surface, profiling, or the final finish pass. Include the workholding arrangement and the intended holder. These details give a supplier a useful application to review.

Build a shortlist you can compare

Create a table with a column for the complete insert code, manufacturer grade, chipbreaker, source page and proposed operating range. Keep each manufacturer’s names as written. Avoid translating one brand’s suffix into another brand’s recommendation without a documented cross-reference.

Decide which alternatives actually fit your holder before comparing prices. Separate an insert that can be stocked for the present job from a candidate requiring another holder or setup. That distinction prevents an attractive catalogue option from becoming an unplanned tooling change.

Keep the trial measurable

Write down the approved starting parameters and how the first part will be checked. During the trial, record the part result and the reason for each adjustment. Preserve the initial settings so another operator can understand what changed. A useful process record is more valuable than a generic claim that one grade is “best.”

Our insert guide brings the shape and material decisions together. The turning calculator converts your chosen cutting data into RPM and feed.

Material classification reference: Sandvik Coromant workpiece materials.

Frequently asked questions

Does an ISO material group identify the exact insert grade?

No. It narrows the application family. Record the alloy, hardness, operation and cutting conditions, then use the toolmaker’s grade and geometry recommendations.

Can the same insert shape be supplied in different grades?

Yes. Shape and grade are separate selection decisions. Read the full product designation and compare the manufacturer’s application data before ordering a replacement.