How to Avoid Distortion when Quenching Aluminum Parts
Advice from the Experts at Jones Metal Products
aluminum-heat-treating | October 19, 2018 |
At Jones, our heat treating services have become a cornerstone of our service offerings, along with hydroforming and fluid cell forming. We’re proud to offer these capabilities in house, and in our decades of experience, we’ve seen that these best practices keep our Nadcap heat treating services operating at their finest. If you use heat treated parts, here are our recommendations to avoid part distortion when quenching.
Orient Your Parts for Even Quenching
By strategically filling the drop bottom furnace basket, our customers see two benefits: more parts can be treated at once and distortion can be avoided. To illustrate this point, we like to use an anecdote that comes from our own experience. A customer with orders of metal tubes came to us because their previous hydroforming company was delivering heat-treated parts with unexpected curvature. We discovered that the customer’s metal tubes were being loaded vertically into the basket. Because the entire part was not being submerged at once, the bottom of the tube was cooling before the top of the tube; this uneven cooling was warping the parts. After changing the orientation of the tubes in the basket, the horizontally-placed parts were evenly cooled by the quenching solution, preventing distortion.
When baskets are dropped from our furnace into quenching solution, parts are rapidly cooled—it takes about six seconds from the moment the furnace door is opened. Because this process happens so quickly, it’s important to consider the position of parts in the basket in advance to avoid distortion.
Use Glycol in Your Quenching Solution
At Jones Metal, we can quench with glycol solutions, hot water, cold water and air. When customers bring us specifications for quenching their metal products, we’re prepared. Across the industry, we’ve seen that a water and glycol solution works well because it helps remove air bubbles from the surface of parts quickly. For example: if we heat treat a baking pan, the flat surface of that pan can trap air and stop the quenchant from touching the metal. If the quenchant can’t reach the metal, it won’t cool—this causes distortion. However, a water and glycol solution whisks bubbles away from the part’s surface.
Some say that because glycol is expensive and needs periodic replacement, the cooling property of water alone is sufficient and that glycol isn’t necessary. But for many of our customers, the mentality that glycol isn’t worth the money investment simply doesn’t hold water. This solution helps prevent distortion and provides better results overall and for them, that’s more than worth the investment.
Heat Treating at Jones Metal
Are you looking for a trusted partner for heat treating? Call us today to speak to an expert or submit your specifications.