90° Square Shoulder Insert Grades and Selection Guide

APET & XPET Grade Description
Shock & Wear Resistance Uncoated (Base Grade) with Coating Description Specifications
TOUGHEST
Shock Resistance
DMP35 Moderate wear resistance/high shock resistance. Recommended for interrupted or unstable steel applications, most stainless steel and high-temperature alloy applications. ANSI C1-C2, ISO K25-K40, M25-M35
  DMP35-TCI Modified AlTiN – premium medium- to high-temperature coating.
DMP35-GLH Premium AlTiN – higher-temperature coating, very low friction characteristics.
NEW DMP35-HM Use HM for a higher-temperature coating in tough stainless steels.
TOUGH
Shock and Wear
DMK35
NEW
XPET ONLY
Specifically developed for inconel and other high-temperature alloys, as well as demanding stainless steel applications. Also suitable for smoother general-purpose milling in a variety of materials. ANSI C5-C6, ISO M30-M40, P30-P40, K30-K40
NEW DMK35-HM Use HM for a higher-temperature coating in tough stainless steels.
NEW DMK35-IN IN provides the best performance for high-temperature alloys and tough stainless steels. First choice for inconel.
MEDIUM
Shock and Wear
DMK30
XPET ONLY
Micro-grain carbide providing higher wear resistance and moderate shock resistance for applications in tough stainless steels, high-temperature alloys, irons and many tool steels. ANSI C2-C3, ISO K15-K30, M15-M30
  DMK30-TCI Modified AlTiN – premium medium- to high-temperature coating.
  DMK30-GLH Premium AlTiN – higher-temperature coating, very low friction characteristics.
NEW DMK30-HM Use HM for a higher-temperature coating in tough stainless steels.
MEDIUM
Shock and Wear
DMP30 High wear resistance/moderate shock resistance, recommended for most steel and some ductile iron applications. ANSI C5-C6, ISO P25-P40
  DMP30-TCI Modified AlTiN – premium medium- to high-temperature coating.
DMP30-GLH Premium AlTiN – higher-temperature coating, very low friction characteristics.
NEW DMP30-HM Use HM for high-performance milling of tougher steels and tool steels.
HARDEST
Wear Resistance
DMK25 Highest wear resistance with reduced shock-absorption capabilities. Suitable for all materials where cutting conditions are very stable. First choice for hardened steel (> 52 Rc). ANSI C2-C3, ISO K15-K25, M15-M25
  DMK25-TCI PVD AlTiN coating. Appropriate for higher-temperature applications such as high-velocity cast iron machining, tough stainless steels, high-temperature alloys and hardened steel.
DMK25-GLH Premium AlTiN – higher-temperature coating, very low friction characteristics.
NEW DMK25-HM Use HM for the highest hardness in gray and ductile irons, as well as heat-treated steels.

Older coatings available upon request; may have up to a 2-week lead time.

APET & XPET Geometry Selection
APET Geometry Traits XPET Geometry
Positive/negative cutting edge with T-land Cutting Edge Positive cutting edge with a light hone and no T-land
Somewhat free-cutting; meant for higher chiploads (>.005" IPT); creates medium burr Cutting Action Free-cutting, small burr; can run at lighter chiploads (>.002" IPT)
Higher force due to negative edge; will deflect more than XPET Force Lower force due to sharper edge; less deflection
Higher heat generation than XPET; creates more heat at higher speeds Heat Less heat generated due to positive edge
Very strong cutting edge; able to withstand more shock and interruptions Strength Weaker, due to edge sharpness; not able to withstand significant interruptions
Longer edge life due to strong cutting edge; will roll more burr and wear out rather than chip out Edge Life Shorter, due to edge sharpness; may chip out if run too long
APET & XPET Carbide (Uncoated) Grade Selection
Traits DMP35 DMK35 DMK30 DMP30 DMK25
Toughness (Fracture) Very tough, able to withstand shock and interruptions Somewhat tough – able to handle exotics and high-temp. alloys at normal parameters; not as fracture resistant as DMP35 Tough and hard; not as tough as DMP35, but tougher than DMK25 Tough and hard; not as tough as DMP35, but tougher than DMK25 Not as tough; may fracture in abusive applications
Wear Resistance (Edge Life) Softer carbide, will not last as long as DMK25 Outstanding edge life in inconel and exotic materials where temperature control is primary and coolant is used Good - harder than DMP35 but not as hard as DMK25 Longer life than DMP35, but shorter than DMK25 Longer edge life due to higher carbide hardness
Heat Resistance Lower heat resistance due to lower hardness of carbide Good heat resistance due to the fine grain structure of the carbide Good heat resistance - more than DMP35 but less than DMK25 Higher heat resistance than DMP35, less than DMK25 Highest heat resistance
Resistance to Built-Up Edge (BUE) Fair resistance to BUE; some buildup may occur – use coolant as a preventative Excellent resistance to BUE; designed for the most challenging materials where coolant will be used, so BUE will be less problematic Good resistance Poorer resistance to BUE; not typically a stainless steel grade Good resistance
Feed Capability High, due to toughness Feed at general parameters only; not intended for heavy feed rates Average - less feed than DMP35 but more than DMK25 Strong feed capabilities, approx. 20% lower than DMP35 Lower, due to brittleness; run at higher speeds and lower feeds
Coolant Capability Good; toughness gives it more resistance to thermal shock Good; intended for use with coolant Good on high temp alloys and some tough stainless steels Fairly tough; will allow machining with good coolant flow Not as high; may experience thermal shock unless coolant flow is very good
Choose the Best Grade for Your Application
Material Operating Speed Geometry 1st Choice Grade* Coolant
Free machining, low-carbon steels Low to Medium XPET DMP30-TCI Air/Flood
Higher XPET DMP30-GLH Air
Medium-carbon steels, tool steels Low to Medium APET/XPET** DMP30-TCI / DMK30-TCI Air/Flood
Higher APET/XPET** DMP30-GLH / DMK30-GLH Air
All steels – interrupted cuts and heavy roughing cuts All APET DMP35-TCI / DMP35-GLH Air
Heat-treated steels (48-62 Rc) Low to Medium APET DMK25-HM Air
Soft stainless steels (303, 304) Low to Medium XPET DMP35-TCI / DMK30-TCI Air/Flood
Higher XPET DMP35-HM / DMK35-IN Air/Flood
Tough stainless steels (304L, 316, 400 series and PH series) Low to Medium XPET DMP35-GLH / DMK30-GLH Air/Flood
Higher XPET DMP35-HM / DMK35-IN Air/Flood
Cast iron All APET DMK30-HM / DMK25-HM Air
Aluminum alloys, copper alloys All XPET-ALU
XPET-PCD
DMK25 / DMK25-GLH Flood
High-temperature alloys, titanium All XPET DMK35-IN Flood

* Contact Applications Specialist if first choice doesn't work.

** Customer preference. Both are acceptable see cutting edge differences above.

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