Abrasive wear ASTM G65 test results using SuperExpanite Hardening
ASTM G65 Austenitic Wear Test
Outstanding abrasive wear test results on austenitic stainless steel after SuperExpanite Surface Hardening.
Abrasion wear is an extensive problem for stainless steels. In the on-going effort to increase the knowledgebase on abrasion, Expanite requested Bud Labs to measure the dry abrasion characteristics of untreated and Expanite treated samples of austenitic AISI316L using the ASTM G 65 Procedure.
ASTM G65 Standard Test for measuring abrasion
The ASTM G65 Procedure is a standard test method for measuring abrasion using the dry
sand/rubber wheel apparatus where weight loss is used as indicator for the wear resistance:
the less the better.
The results are indisputable: The 316L with SuperExpanite is more abrasion resistant than
the untreated sample approximately reducing abrasive wear by more than 60%.
The table below lists the observed weight losses and thereby the reduction on an Expanite hardened sample:
ASTM G65 Abrasive Wear Test Results
|
Description |
Initial Weight (g) |
Final Weight (g) |
Mass Loss (g) |
Density* |
Volume Loss |
Start |
Finish |
Loss |
AVL |
|
(g/cm3) |
(mm3) |
(in) |
(mm3) |
||||||
|
316 |
160,0465 |
159,9784 |
0,0681 |
7,68 |
8,87 |
8,921 |
8,921 |
0,000 |
8,95 |
|
316 w/ SuperExpanite |
165,3589 |
165,3365 |
0,0224 |
7,68 |
2,92 |
8,921 |
8,921 |
0,000 |
2,94 |
Not just a coating
The Expanite treatment effectively removes the oxide film covering stainless steels. This allows controlled incorporation of carbon and nitrogen atoms in the underlying metal. The hardened layer is characterized by an expansion of the material structure. We call this zone expanded austenite, expanded martensite, or simply, Expanite.
With the Expanite process it’s possible to increase the surface hardness of stainless steels by up to 10 times, while maintaining or even enhancing corrosion resistance. This method is considered unique since it’s suitable for austenitic-, ferritic-, martensitic and duplex stainless steels. Parts can be treated with extremely short lead times—a few days—which is previously unseen within surface hardening of stainless steel.
The Expanite technology can significantly increase the value of products across many industries—from knives, valves, mixers, and grinders for the food industry, to pumps and extruder screws, or injection parts for the automotive sector, as well as screws, bolts, and washers.
At its core, Expanite offers 3 different processes, each of which can be optimized according to customers’ requirements in terms of abrasion, galling, corrosion and scratch resistance. This means that Expanite can develop and customize solutions for a wide variety of companies and industries.
