With hardfacing, check-cracks throughout the weld deposit are a distinctive characteristic of using chromium carbide overlays.
Immediately after welding, as the hardfacing weld deposit cools and contracts with little ductility, check-cracks form along the chromium carbide grain boundaries. This is normal and expected for alloys with this chemistry. In fact, if they did not check-crack, the weld deposit would most likely spall off.
However, there are applications where check-cracks in the hardfacing weld layer would be detrimental to performance of that part, and so they must be avoided. For example;
1. Applications when a crack in the hardface layer might continue into the base material.
2. Applications that require multiple layers or repeated reapplications.
3. Applications where the abrasive material such as soil, metal ores, or other foreign matter might get caught in the check-cracks.
Crack-free hardfacing under Magnetic Particle Inspection
When check-cracking in the hardface must be avoided, DuraHard™ Crack-Free Hardfacing Alloys from Postle Industries are an obvious choice. They have been developed with various chemistries to meet different wear-resistance goals whilst remaining 100% crack-free. They generally exhibit the same or better abrasion resistance compared to chromium carbide hardfacing products, and have the advantage of better toughness and impact resistance.
ALLOY | TYPE WIRE | GAS COVER NEEDED | PRIMARY PURPOSE | WEAR RATING (10 is best) |
DuraHard™2825NC-MCG | Metal-cored / Gas-shielded | yes | Abrasion and impact | 5 |
DuraHard™2826NC-MCG | Metal-cored / Gas-shielded | yes | Abrasion and impact | 8 |
DuraHard™2826NCNb-FCO | Flux-Cored / Open-arc | no | Abrasion and impact | 8 |
DuraHard™2827NC-MCG | Metal-cored / Gas-shielded | yes | Abrasion | 10 |
DuraHard™2828NCTi-FCO | Flux-Cored / Open-arc | no | Abrasion and impact | 8 |
DuraHard™2898-MCG | Metal-cored / Gas-shielded | yes | Abrasion and impact | 3 |
DuraHard™2899-FCO | Flux-Cored / Open-arc | no | Abrasion and impact | 3 |
Super Edge | Metal-cored / Gas-shielded | yes | Cutting edge retention | 7 |
Some specific examples of applications that benefit from a crack-free weld deposit include cement, slag and ore roller presses and grinding rolls, drill pipe, cutting and shredding knives, shredding hammers, agricultural tillage tools, rendering equipment, bucket pins, stabilizers, debarking hammers, and vertical shaft impact crusher rotors.
Please contact us or visit our brand new website www.hardfacetechnologies.com for more information.
North/South/Central America, Asia, Africa, and Australia
Mike Korba; mkorba@postle.com
+1 216-265-9000
5500 West 164th / Cleveland, Ohio 44142
Europe/Russia/Middle East
Colin Duff; colin.duff@hardbandingsolutions.com
+44 1294 446017
North Ayrshire, Scotland KA12 8LN