Aluminum Welding Guide

If post-weld anodizing is to be performed it is important to select the correct filler metal to match color with a base metal after anodizing.

The classic example of what NOT to do is to weld 6xxx series base metals with 4xxx filler metals and then anodize the end product. The 6xxx series base metals will anodize bright and clear while the 4xxx filler metals anodize dark and gray in color because of the free silicon content in the 4xxx series alloys. Refer to the list of alloy chemistries on page 10 of this booklet and follow the recommendations in the column for post-anodized color. Also, evaluate the ratings for color match after anodizing in the aluminum filler metal selection chart in the back of this booklet.