ISO 513 application group · brand-neutral
ISO S grades — superalloys & titanium
Two different S scales, and they are not the same. On a workpiece chart, S plus a number describes the material you are cutting. On an insert box, S plus a number describes what the grade is built for. The letter is shared, so a S-group material is cut with S-group grades. The numbers are not: a workpiece subgroup number and a grade's application number come from different scales and must never be matched to each other. Everything on this page is the grade side.
ISO S is the superalloys & titanium group. 75 grades from 13 manufacturers are placed somewhere in it across 7 application classes, according to the comparison charts the makers publish themselves.
What the number after the S means
Inside a letter the two-digit number is a position on one axis: the low numbers are the wear-resistant, harder grades meant for finishing cuts at higher speed and lighter load, the high numbers are the tougher grades meant for roughing, interrupted cuts and less stable setups. It is a continuum, not a set of boxes, and makers place their own grades on it.
Grades at each S class
Two grades in the same class are built for the same job. They are not identical: substrate, cobalt content, coating and edge preparation still differ, and so will tool life and the cutting data you should start from.
S01
3 grades from 3 manufacturers are placed at S01: ISCAR IB05S · Mitsubishi MB730 · Tungaloy BX950.
S05
11 grades from 9 manufacturers are placed at S05. The 4 below have a cross-brand equivalence page: ISCAR IC806 · Sandvik GC1105 · Tungaloy KS05F · Walter WSM01 and 7 more.
S10
31 grades from 12 manufacturers are placed at S10. The 13 below have a cross-brand equivalence page: Dijet JC8015 · ISCAR IC806 · Kennametal KCS10 · Kennametal KCS10B · Sandvik GC1105 · Sumitomo EH510 · TaeguTec K10 · TaeguTec TT3010 · TaeguTec TT5080 · Tungaloy AH8015 · Tungaloy KS05F · Walter WSM01 · Walter WSM10S and 18 more.
S15
15 grades from 8 manufacturers are placed at S15. The 4 below have a cross-brand equivalence page: Seco TS2500 · TaeguTec TT3010 · Tungaloy GH110 · Walter WSM10S and 11 more.
S20
28 grades from 12 manufacturers are placed at S20. The 7 below have a cross-brand equivalence page: Dijet JC5015 · Kennametal KC5025 · Kennametal KCU25 · Sandvik GC1125 · Sumitomo EH520 · Tungaloy AH630 · Walter WSM20S and 21 more.
S25
18 grades from 11 manufacturers are placed at S25. The 5 below have a cross-brand equivalence page: Dijet JC5015 · Kennametal KC5025 · Kennametal KCU25 · Sandvik GC1125 · Walter WSM20S and 13 more.
S30
3 grades from 3 manufacturers are placed at S30: Mitsubishi VP20RT · TaeguTec TT8020 · Walter WSM30S.
Where these numbers come from
Every placement above is read from a grade comparison chart published by a manufacturer, cross-checked against other makers' charts. Nothing is inferred from price, availability or popularity, and no manufacturer pays to appear here. Something wrong on this page? research@cuttingtoolsai.eu.
Looking for the workpiece side instead — which steel, stainless or iron falls in which group? That is the ISO material groups chart.
Are you overpaying on your ISO S inserts? Paste your insert list and get a cost audit in about 30 seconds: cross-brand equivalents at the same ISO application position, and where you are likely overpaying. No signup, no sales call.
Ask about your own case
Material, operation, machine — get a grade and a starting cutting data set, grounded in the same reference data.