Coated Electrodes for Tool Steels
Procedure
- Identify the tool steel to be welded. While there are many variations of the tool and die steels, the most common are: 
- Prepare the surface to be welded. Remove all foreign matter and rough edges. Make sure that only the original base metal is exposed. 
- Select the proper electrode per the chart. Preheat the tool steel to be welded per the chart. 
- Use AC or DC, reverse polarity, with the lowest possible amperage setting for good fusion. 
- Using a striker plate, carry the arc to the area to be welded. 
- Maintain preheat temperature while welding. 
- Two or more passes should be used to minimize dilution of the base metal. Peen each pass rapidly to stress relieve. 
- Postheat or temper the deposit per the chart. 
- If heat treating is desired, use the annealing, hardening and quenching recommendations in the chart. 
- For checking proper welding temperature, use a temperature indicator. 
- With reference to "Step 7" above, Aufhauser SUPERBLUE is recommended as a "cushioning" or "padding" pass adjacent to the base metal. This minimizes dilution of the base metal and offers a softer, more ductile alloy next to the higher hardness base metal. Aufhauser SUPERBLUE does not respond to heat treatment, so it should not be exposed to the finished weld area. 
| Water hardening | W-1 through W-5 | 
| Oil Hardening | O-1 through O-6 | 
| Air Hardening | A-2 through A-10 | 
| High Speed | M-1 through M-44 | 
| Hot Work | H-10 through H-43 | 
Packaging: All sizes are packed in five pound tubes, four tubes per twenty pound carton.
Use the following chart as a guide in the effective and economical salvage of costly tools and dies:
| Tool Steel to be Welded | Aufhauser Covered Electrodes | Sizes (Inches) | RC Hardness as Deposited | Preheat °F | Anneal °F | Harden °F | Post-Heat °F | Quench | 
|---|---|---|---|---|---|---|---|---|
| Air Hardening | 4-AH | 3/32 1/8 5/32 | 48 - 52 | 300 - 1000 | 1500 - 1600 | 1750 - 1850 | 300 - 1000 | Air | 
| Oil Hardening | 4-OH | 3/32 1/8 5/32 | 48 - 56 | 250 - 400 | 1425 - 1450 | 1425 - 1500 | 250 - 400 | Oil | 
| Water Hardening | 4-WH | 3/32 1/8 5/32 | 52 - 58 | 275 - 450 | 1425 - 1450 | 1425 - 1450 | 275 - 450 | Water | 
| High Speed Steel | 4-HSS | 3/32 1/8 5/32 | 58 - 63 | 1000 | 1600 | 2200 - 2225 | 1000 | Oil | 
| Hot Working | 4-HW | 3/32 1/8 5/32 | 52 - 55 | 900 - 1200 | 1500 - 1600 | 1750 - 1850 | 900 - 1200 | Air | 
| Flame Hardening | *4-FH | 3/32 1/8 5/32 3/16 | 45 | 800 - 900 | Use S.A.E. 4130 Procedure | |||
* This value is not as deposited. Aufhauser 4-FH can be flame hardened up to 45 RC
