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I will be welding (2) D2 flats to an 1144 stressproof shaft (ASTM A311). The D2 flats are 1/2" thick X 3" wide X 18" long and the 1144 shaft is 2-3/16" dia x 38" long. The shaft has (2) flats milled on it, 18-1/2" long and 90 degrees apart, for the D2 to set on and be welded to. I'm not a welder, but I need to develop some welding specs for this operation that our welders in the shop can follow. I have found some information on preheating the D2 and all, but nothing about welding these two materials together. If you have any suggestions or information I'd appreciate your response. Thanks.
Reply:Why?What are you trying to make or accomplish?D2 is a high-carbon high-chromium air-hardening tool steel. 1144 is a high-sulfur cold-worked nitrogen-alloyed steel from LaSalle, used for inexpensive (relatively) shafting.Welding high-sulfur steel is not a good plan. Welding a tool-steel is not all that good either. Combining the two steels in a weld is not a good plan at all.IMHO.
Reply:Well, I need the D2 due to its abrasion resistance. It will be moving machine scrap turnings across some stationary cutting teeth in order to cut or shear the scrap turnings. The shaft I'm using for its high yield strength. Could you tell me more about why it's not a good idea to mix these two metals? Perhaps suggest another to replace either the 1144 shaft or the D2 flats? Thanks for your thoughts and suggestions.
Reply:You may want to make the shafts out of 4140..It will be more "compatable"...zap!I am not completely insane..Some parts are missing Professional Driver on a closed course....Do not attempt.Just because I'm a dumbass don't mean that you can be too.So DON'T try any of this **** l do at home.
Reply:A high-sulfur steel is prone to cracking after welding (hot cracking), because of the sulfur. The sulfur is added by the steel mill to make the steel easier to machine, but the sulfur ruins (IMHO) the general properties of the steel. Properties like yield strength and fatigue stress. There are filler materials made for welding high-sulfur steels, they have flux/slag formulas to reduce the sulfur in the weld.A high-carbon tool steel is prone to cracking after welding, because of the carbon and the hardness of the tool steel. Pre-heat and slow cooling and low-strength filler materials help to minimize cracking here.A yield strength of 100 ksi is really not all that high, in my book anyway. A quick check on matweb shows over 2000 metals (metals, alloys, and/or heat-treatments) with a yield strength equal or greater to 100 ksi.If you need the cutters to be replaceable, look into a bolted arrangement instead of a welded connection. This way you can have a strong and durable shaft and still have hard and abrasion-resistant blades that can be replaced. And you don't have to deal with heat-treating the entire assembly, just the knives. Or buy the knives heat-treated to your specs and then EDM or laser cut the mounting slots/tabs/holes in the hard blades.
Reply:Thanks for your input, I think I have to go in another direction. Am considering (now) using more compatible steels for the shaft and flats, but at the cutting area add some hard weld (which the welders out back are used to doing) and machine/grind it as needed. Thanks again for your insights.
Reply:What MoonRise says makes alot of sense. |
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发表于 2021-9-1 00:58:31