In 2006 we imported Bohler N690 for testing. The tests were great but our cost of shipping steel from Austria made the steel price too high. In 2010 we worked with Bohler Uddeholm (BU) to introduce their steels to North American knifemakers.
I need to clarify the meaning of "Microclean". This is the term BU uses to specify their powder metallurgy steels. BU is producing the 3rd generation of powder metallurgy steels. The 1st generation was the typical powdered metals with coarse granules. The 2nd generation reduced the granule size to the size about the consistency of flour. The 3rd generation runs the fine powder through an electromagnet to get rid of particles that are not steel. Steels made from 3rd generation powders are very clean with evenly distributed elements.
The steels BU is promoting are:
• Elmax PM Stainless Steel
• K110 (D2)
• K294 (PM A11)
• M390 PM Stainless Steel
• N680 Cast Nitrogen Stainless Steel
• N690 Cast Stainless Steel
• S690 (PM M4)
• Vanax PM Nitrogen Stainless Steel
They have other steels and we have received a few for testing.
BU has been testing their steels and has released the results. Here are links to two of the tests:
CATRA Test Results:
http://www.bucorp.com/files/CATRA_Test_Results.pdf
Toughness Test Results
http://www.bucorp.com/files/Toughness_testing_for_knife_steels.pdf
The CATRA test results very interesting. Various blade steels were sent to CATRA to test the edge holding. CATRA did not know the steels being tested. The samples were marked with codes rather than steel designations. Two stainless steels, M390 at HRC 61+ and Elmax at HRC 62 out cut CPM M4.
The CATRA test results also show N690 (a cast steel) out performing 440C, 154CM & CPM154 by 28%.
The toughness tests show Elmax is tougher than any other stainless blade steel by a significant margin.
The new steel introduced this week is Vanax. It was going to be called Vanax 35 but the name was shortened. It is the first powder metallurgy nitrogen stainless steel. We sent a knife made with 1st generation powder to be tested. The test results showed edge holding better than S30V:
http://www.bladeforums.com/forums/showthread.php/793481
The production Vanax uses 3rd gen powder. It can be made harder for better edge holding without chipping.