Should You Hardface AR400?
Did you know…
• Most AR400, AR450 and AR500 available on the market do not have the same hardness throughout the thickness of the steel.
• Most people are not aware AR400, AR450 and AR500 have No Industry Standards.
You Should Never Do This To AR Type Steels:
NEVER hardface any heat treated wear steel such as AR400, AR450, AR500 etc., with a Chrome Carbide hardfacing welding rod or wire.
Here is why:
Heat treated steels have additional alloys, which are dramatically higher in strength than regular mild steel.
It is important to realize the difference, because the carbide hardfacing is designed to have these ‘stress checks’. When applying to mild steel with a tensile strength of 36 ksi to 50 ksi, those micro-cracks in the hardfacing don’t affect the base plate at all.
Here you can clearly see the micro cracks in the Chrome Carbide deposited onto the mild steel base plate. Notice on the sides how the cracks do not continue into the base plate. Carbide hardfacing is designed to have the micro cracks across the weld beads, allowing them to hang onto the base plate and not chunk off.
On the other hand, heat treated alloy steel wear plates have a tensile strength range of 200 ksi to 240 ksi!
What Happens To Those Micro Cracks When You Weld On The Surface Of High Strength Steels?
The Crack Continues Into The AR Steel, Until It Completely Fractures And Your Plate Fails.
So, What Should You Use Instead For Spot Repairs Or Touch Ups?
JADCO’s line of Fusion ™ Welding Alloys are ready to deliver great results for every type of wear plate.
We have several non-carbide hard facing products to choose from. Each Fusion ™ Welding Alloy is selected based on the type of wear challenge you battle. Is it abrasion, impact or corrosion?
It is also important to realize YOU SHOULD NEVER APPLY HARDFACING DIRECTLY OVER OLDER HARDFACING.
Hardsurface directly on top of hardsurface, rarely results in a secure weld. The new weld deposit often chips off, so your material and labor investments are lost.
What is referred to as a Butter Pass needs to be between the new and old hardfacing. Think of applying butter between two pieces of bread, to help them stick together. Some also call this a Cushion Layer.
Universal has good resistance to impact and corrosion.
FUSION ™ Universal is available in both a wire versions and as a stick electrode versions.
Once you have the cushion pass in place, you are ready for the hardfacing layer.
For AR type of steel wear plates we recommend Fusion ™ GO.s
NOTE: EVERY Chromium Carbide hardfacing product on the market contains dangerous hexavalent Chromium.
According to the National Institute of Environmental Health Sciences:
‘Some of the adverse health effects from hexavalent chromium exposure includes: nasal and sinus cancers, kidney and liver damage, nasal and skin irritation and ulceration, and eye irritation and damage.’
Because Fusion ™ GO doesn’t contain any hex Chrome, you not only minimize potential health issues, it develops no stress micro crack problems associated with Chrome Carbide Hardfacing. It’s A Double Win.
Use Proper Welding Practices
– It Must Be Clean And Dry Before Starting
Do not weld hardfacing over existing hardfacing without a cushion pass that is compatible with both materials.
Always weld on clean shiny metal. When you remove 1/16” off of the worn surface with a grinder, you now have solid clean metal to be welded.
All cracks/cracked areas must be removed before you preheat and weld. This surface will have no structural integrity due to the micro cracks. Remove this area with a grinder down to solid metal.
Do not weld over rust, paint, dirt, oil or grease. If you cannot take the time to prepare the weld area correctly; you will have to do it all over again in the future.
Always Weld Safely
- Ventilation – have adequate air movement so you minimize inhalation hazards.
- Use personal protective equipment including: protective welding clothing; welding gloves, eye protection, steel toe shoes, welding helmet with correct darkness shade and skull cap. Other safety equipment may be required for specific projects or locations.
- Equipment – Verify all electrical components are secure with tight connections and no exposed electrical wires. Have the correct shielding gas for the welding wire you will use.
- Verify any flammable items are removed from the area. If they cannot be removed, shield them with welding blankets or barriers. Have adequate fire extinguishers readily available and be certain your crew knows how to use them.
For the past 43+ years, JADCO has provided the longest lasting wear resistant steel to heavy industry. As the industry leader, we know what will deliver the best results for your equipment.
We pride ourselves to deliver “Walk Away Results” to you. This means we are both able to walk away after you install JADCO wear resistant steel products, knowing you will not lose any sleep wondering if these wear products will fail in your equipment at the worst possible time. Not with JADCO.
At JADCO, we think differently by strictly focusing on your results. Now you can understand why JADCO delivers better performance results for our customers.
Allow us to help you today by calling 724.452.5252, or email info@jadcomfg.com.
We will schedule a meeting with one of our local wear plate specialists at a time that best fits your schedule.
Remember, the only thing you have to lose by not working with JADCO, are your profits.
