Aluminum Oxide, Hardness

January 9, 2023 – 05:27 am

How to define the hardness of the aluminum oxide

The image to the right shows a cross section of a hard anodic coating with Vickers indentations and thickness measurements.

The pyramid has to be square formed to be sure of hardness value measured.

The light blue to the left is the aluminum alloy and the dark to the right in the picture is the resin.THE MILITARY SPECIFICATION, MIL-A-8625F, for “Anodic Coatings for Aluminum and Aluminum Alloys” says nothing about any requirements of the hardness of Type III – Hard Anodic Coatings, see earlier post about this subject here.

The European Standard EN 12373 ”Aluminium and aluminium alloys – Anodizing” has none either. Both of them have on the other hand requirements of a wear resistance of the coating.

The maximum wear index for coatings on aluminum alloys having a copper content of 2 % or higher is of 3.5 mg/1000 cycles and 1.5 mg/1000 cycles for all other alloys.

Next post will discuss the wear resistance versus the hardness of hard anodic oxide coatings.

Source: aluminumsurface.blogspot.com

Read electro-mechanical engineering blog

SAIT 60316 Closed Coat Aluminum Oxide 1-Inch x 42-Inch LA ...

Shop Fox D1423 1/2" Diameter by 6" Aluminum Oxide Hard ...

Woodstock D1323 9-Inch Diameter PSA 100 Grit Aluminum ...

3M Hookit Paper Disc 236U, Hook and Loop Attachment, Aluminum Oxide, 5" Diameter, P320 Grit (Pack of 50)
BISS (3M)

Hookit discs are easy to change and reuse
Hook-and-loop feature provides reliable attachment
Strong, C-weight paper backing provides extra durability when compared to lighter weight paper backings and is suitable for portable sanders
Aluminum oxide mineral is durable, cuts fast, and performs well on many surfaces
Load-resistant coating helps prevent premature loading of the disc surface to maximize cut and extend the life of the abrasive grains

3M Stikit Paper Disc 735U with Tab, PSA Attachment, Ceramic Aluminum Oxide Bland, 5" Diameter, P100 Grit (Pack of 50)
BISS (3M)

Ceramic/ aluminum oxide blend self-sharpens at a high rate and has exceptional durability
Stikit adhesive on a C-weight backing allows quick, easy application and removal while resisting tears
Tabs are easy to grab for quick liner removal
Load-resistant coating helps prevent dust and debris from clogging the abrasive for better cut-rate and longer disc life
Resin bond resists heat to prolong the life of the disc

Washington Mills Recycling Spent Aluminum Oxide

3-1/4" (83MM) Flex Hone 320 Grit Aluminum Oxide Review

Aluminum Oxide Sanding Belts, 4-inch by 24-inch, 36 Grit ...

	Fundamental Rockhound products: 1 oz .03 Micron Aluminum Oxide Linde A - Lapidary Rock Polish BISS (Sister's Rocks LLC) 1 ounce Aluminum Oxide polish, mesh size .03 micron 99.9% Pure Grade Also known as Linde A Mohs Hardness 9
	PuriTEST Acid Purity Test for Gold/Silver/Platinum, Plus Digiweigh Digital Lab Scale, 1000g x 0.1g Jewelry (PuriTEST, DigiWeigh) Genuine DigiWeigh 1BX Deluxe Jeweler s Scale with Lifetime Warranty Capacity x Readability: 1g x 0.1g / 35.3oz x 0.01oz / 15432gn x 1gn / 5ct x 0.5ct / 643dwt x 0.1dwt / 32.1ozt x 0.01ozt Complete PuriTEST acid test kit with glass pro-stone Very easy to use & includes instructions. Test purity of Silver, Gold, and Platinum This set is popular among professionals, and yet also ideal for hobbyists and beginners
	3M NX PSA Paper D/F Disc Roll, Aluminum Oxide, 6 Holes, 6" Diameter, P120 Grit (Roll of 100) BISS (3M) Six-hole design allows dust evacuation from the disc surface to prevent loading, increase productivity, and provide a cleaner work environment (when used with a... Adhesive backing provides easy attachment and roll form provides grab-and-go convenience Durable paper backing is suitable for dual action or random orbital sanders (D-weight paper for grades 40, P60, P80; C-weight paper for grades P100-P800) Aluminum oxide mineral is durable, cuts fast, and performs well on many surfaces Load-resistant coating helps prevent premature loading of the disc surface to maximize cut and extend the life of the abrasive grains