Coatings on end mills, what to use for what material?

[moonlight machine]

When you look on line at end mills there is a dizzying array of coatings available but very little information on what should be used for what material. What sort of coatings are you using and what are you using them on?

 

[partsproduction]

I think it's funny that no one answered right away, that tells me that most of us don't know as much about it as the tool salesmen do.

Or maybe people were thinking a tool salesman would answer it, and they are all having cocktails.

 

[moonlight machine]

I think it's funny that no one answered right away, that tells me that most of us don't know as much about it as the tool salesmen do.

Or maybe people were thinking a tool salesman would answer it, and they are all having cocktails.

I think it is a mystery to most guys. They just get what the salesman says and they don't know what any of it is all about.

 

[Mike1974]

aluminum - high polish uncoated, TiN, TiB2

Honestly, TiALN, TiCN, ALTiCN, etc... not sure, other than they work on 'steel'. No idea what is best for stainless vs iconel vs titanium, etc etc...

edit; I probably screwed up some of those letters... (?)

 

[adama]

My experiance, the gold of TIN may look flasher, but the grays - blacks of AlTiCN (or its various flavours) work well here. Using nothing but air blast and speed in steels. Prefer PVD deposited too over CVD as the edges get to remain sharper and the bits cut easier.

 

[AARONT]

This is what's worked for me.

Bright, ZrN, and TiB2 for aluminum, titanium, and brass
AlTiN, TiAlN, and Firex for carbon steels, tool steels, and alloy steels Ran dry if possible
TiN, NaCRO, and TiCN for stainless

 

[Kadlec10]

There are considerations to be made for equipment and speeds/feeds, but the basics I follow for milling are:

In Alum: bright/polished or TIB2. TIB2 is great, but does not seem readily available from my fav local distributors so I only special order for long runs. I have actually never tried a ZrN.

In Reds: Bright/Polished are all I've used and they work great.

In LowCarbon steels: TiAlN or AlTiN, ran dry and fast with a bit of airblast. Push the Speed/feed. Otherwise uncoated or whatevers sitting there... I never really specify TiN- will use, but the benefits have never astounded me. (I've tried TiCN and didnt get great results. Recently learned TiCN cannot handle heat so well; it is an "old tech" coating and was engineered around a slow/low-powered machine. If you're on a bridgeport TiCN is a good choice.)

In Stainless & Alloy Steels: Again with the AlTiN. Run dry with air. In H1150 17-4 a dry AlTiN mill almost tripled my tool life over uncoated with flood. Running one in annealed 4140 now (dry w/air) and its been cutting for 40 of 90sec cycles the last 13 hrs.

From a recent seminar with Orelikon Balzers I learned AlTiN hardens to near diamond-like as it heats up. It actually fails at about the same heat level the carbide binder fails. TiCN fails at about the heat level AlTiN gets good.

AlCrN is an update to AlTiN and sounds like something to try, but I've not gotten into it yet.

 

[rcaffin]

Do not use TiAlN on aluminium. Strange sticky things happen between the Al in the coating and the bulk aluminium. I haven't seen AlTiN but the same would apply. Zr coatings are recommended for Al.

Cheers
Roger

 

[litlerob1]

My problem is that I am not a scientist and can't remember all the chemical abbreviations for all the different coatings, they all seem to look similar in print and the words associated with them aren't a great phonetic representation of the printed representation of the chemical makeup. Let alone all the different parameters for each chemical compound. People like Carbide bob know this shit, but that is his business. I use a dark coating for Steel and no coating for Alu. Same with taps.

Robert

 

[Bobw]

Do not use TiAlN on aluminium. Strange sticky things happen between the Al in the coating and the bulk aluminium. I haven't seen AlTiN but the same would apply. Zr coatings are recommended for Al.

Cheers
Roger

You shouldn't, but you can.. I'm doing it right now, I can hear the chips moving as I'm typing.
You do end up with a weird aluminum smear on the flutes, and I only do it when I need a specific
radius, and I only stock oddball corner rad endmills for steel.. I don't do enough aluminum to
stock that shit too...

My understanding of endmill coatings, and its probably all wrong.. AlTiN, TiAlN. As far
as I'm concerned, its the same damn thing, somebody had to be "cool" and change it up..
The dark purple stuff.

When it gets HOT, like really F'n HOT!!! 1700F'ish.. It gets harder than hell, I vaguely
remember reading well over 100+ on the C-scale, and it gets slicker than snot. I'll run
this on dry on mild steels, 4140's, 1018 type stuff. Wet in Ti, and stainless.. Depending
on how you are running you can get away with dry and faster on some stainless. 17-4 is an
odd duck, in the solution treated state it behaves very much like a "stainless", but once
heat treated it loses almost all of its "stainlessy" properties (cutting wise) and responds
more like a carbon steel, and is perfectly happy running dry.

Then you have the light purple pink stuff TiCn, comes into play at a lower temp.
Haven't used this in years, though I would use it on aluminum, and on steels when
I was hanging out and running slow and wet.

Then you have TiN, the gold stuff that comes on chinese endmills.. They sell it down
at the hardware store in the spray paint aisle.. Its labeled as "Gold Spray Paint".
Apparently it does something, but I dont' know what.

Coatings for aluminum, I don't have a clue..

There is also all kinds of new fandangled BS out there, and I'm sure a lot of it works a
treat.. But I don't have time to deal with all that crap... Pick up the phone or fire
off an e-mail.. "Send Me Something That Will Do XXX"

 

[bmikkalson]

I've tried several magic bullet coatings. I've never been Omg that is amazing!!!
In fact I was just turning some SS and my buddy says ,u have to try this. It lasted as long as my brazed insert .
Totally could be me..

 

[Atomkinder]

Here you go, Google search for "end mill coatings" brings this up as the first result (although maybe my browsing history influenced it.. who knows): Harvey Tool - Coating Chart for Ferrous and Non-Ferrous Materials

General rule of thumb: don't use coatings with aluminum in them for anything aggressive in aluminum. Funny reactions, things get sticky when the workpiece material gets hot and the coating gets hot with it. They need to oxidize in steels (at 1400°F) and become much harder than the carbide substrate of the mill as Bob said. I'm guilty of using corner condition AlTiN tools in aluminum... but who wants multiple same-size chamfer mills lying around? Doesn't matter enough, nothing gets all that hot when you're making a .004" deburring pass.

TiAlN and AlTiN are different in the way they are applied I believe, and have slightly different optimal operating conditions but I just run 'em the same. I'm not trying to get an extra four seconds out of a toolpath over 1000 parts so we'll never really reap the benefits of one over the other, assuming there is a practical one anyway.

This tool company sure lays out some differences, but my experience can't speak to them: Titanium coatings TiN, TiCN, TiAlN, AlTiN - HANNIBAL CARBIDE TOOL, INC.

We've moved away from ZrN coatings in aluminum, a 12k spindle just won't generate the surface footage necessary to need it IMO, but that's what it's for.

TiCN has a few uses as I understand it, but there are companies that also sell it for use in aluminum tooling (YG comes to mind readily), again, probably not worth it in that application.

We don't really do anything fancy so no knowledge outside of general steels, aluminum, easy plastics and some tool steels (but that was the last job).

 

[Shop Supply Guru]

A lot of you nailed it on the aluminum coatings & the common Altin coatings. I will chime in on the new stuff as I sip on my cocktail since I am a salesmen that is what I drink apparently haha.

Most of the newer high end stuff have moved up from ALTIN to AlCroNa & AlNova from Balzers. Or a Nacro coating which is the Platit version of Acrona.
Here is a link about
AlCroNa <--- click
& AlNova <--- click
Platit Nacro <--- click

I sell a lot of Gorilla Mill end mills and they make up a nonesense name called GMX-35 but it is really AlCroNa. Then they have the step up GMS2 which is AlZona which I am guessing is a special blend for them because nothing shows up on Balzers website. I can't blame them for the marketing of special names of their coatings because just about everyone else makes up a name for their stuff or they just don't tell you anything about it.

Anyway with these coatings they are Altin on steroids. The jump from Tin to Altin is HUGE but the jump from Altin to AlCroNa or Nacro is a pretty big step. For example a common Altin has a maximum working temp of 1300*F while AlCroNa is good up to 2000*F before it is toast. The Nanohardness in Gpa of Tialn is 28 while AlCroNa is 32. I am told the AlCroNa has a HRC of 89 while the AlZoNa used by Gorilla Mill has a hardness of 92 HRC.

 

[gwilson]

Na NaNano Alnoanothreoujhlergrltilmnt!!!!

 

[Shop Supply Guru]

Na NaNano Alnoanothreoujhlergrltilmnt!!!!

That's the best of that best!

 

[DDoug]

I got some surplus lathe inserts (basic triangles) but with an awful looking flat black appearance
(like hi heat paint)

Damnedest things are great on rough flame cut work, they take a tremendous abuse.

Any ideas what coating it is ? Would like to find some more.

 

[HuFlungDung]

For some reason, I care more about coatings for lathe inserts than for end mills. The concentrated focus of the cutting action at one small area of the insert stresses the coating far more than the occasional pass that an endmill tooth makes through the part. 90% of the time, the endmill tooth is just going for a ride.

The geometry (variable, corncob, sharp!, flute polish) of the endmill seems more crucial to success for my run of the mill stuff. Some coatings have a bad habit of flaking off right at the flute (on brand new tools) where they are needed. At arm's length, the tool looks fine, but under a microscope, you'd wonder.

 

[DMF_TomB]

any manufacture of tooling usually has page in catalog explaining

 

[Hazzert]

Na NaNano Alnoanothreoujhlergrltilmnt!!!!

Oh the new Nano Sodium coating? I hear you need to run that one dry otherwise it get 'splodey.

 

[plastikdreams]

Do not use TiAlN on aluminium. Strange sticky things happen between the Al in the coating and the bulk aluminium. I haven't seen AlTiN but the same would apply. Zr coatings are recommended for Al.

Cheers
Roger

back when i was first starting out they handed me a new 6 flute supermill TiAlN coated...i made a quick high speed aluminum pocket program...and destroyed the mill in seconds lol...i keep it in my box to remind me.