TECHNICAL DATASHEET PRODUCT OVERVIEW DESIGN APPROACH VECALLOY 752 PERFORMANCE. ASTM G65A: grams lost (low stress abrasion)

T EC HNI CA L DATA SH E E T PRODUCT OVERVIEW Vecalloy 752 is an Fe-based alloy which has been specifically designed to replicate the microstructure o...
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T EC HNI CA L DATA SH E E T

PRODUCT OVERVIEW Vecalloy 752 is an Fe-based alloy which has been specifically designed to replicate the microstructure of tungsten carbide PTA overlay. However, the well-known high performance m i c r o s t r u c t u r e o f W C / N i P TA h a s b e e n substantially improved in Vecalloy 752. Vecalloy 752 grows extremely hard, near spherical, tungsten boride particles throughout the entire weld bead thickness. These tungsten boride particles are harder and smaller than the

tungsten carbide in PTA welds, a characteristic that creates enhanced wear and impact resistance. Specifically, the impact resistance of Vecalloy 752 is up to 30X that of conventional hardfacing products, including WC-based, CCO (chrome carbide overlays), and nanostructure forming steels. Vecalloy 752 is patent pending.

DESIGN APPROACH The design process for Vecalloy 752 and all SCOPERTA materials involves a proprietary high throughput computational metallurgical process to evaluate millions of candidate alloy compositions. Potential candidates are then experimentally evaluated using an advanced screening process where both properties and alloy microstructure are measured. The combined computational and experimental approach allows SCOPERTA to rapidly design the final material with a much better accuracy than conventional experiment-based methodologies.

Vecalloy 752 at 1,000X

VECALLOY 752 PERFORMANCE

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ASTM G65A: 0.06 – 0.08 grams lost (low stress abrasion) Hardness: 66-70 HRC Impact Resistance: >6000 20J Impacts to Failure Hard Boride/Carbide Fraction: >50%

~2600HV Complex Tungsten Boride Particles, Harder than Tungsten Carbide

11760 Sorrento Valley Road, Suite D, San Diego CA 92121 USA Phone (858) 704-4013 Fax (858) 704-4014

Justin Cheney, PH. D [email protected]

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T EC HNI CA L DATA SH E E T

VECALLOY 752 FORMS A MICROSTRUCTURE SIMILAR TO WC/Ni—BUT AT A FINER SCALE Vecalloy 752 is the first hardfacing alloy which pairs the toughness required for high impact applications while competing with the most wear-resistant coatings available. Vecalloy 752 forms microstructure which looks similar to WC/NI PTA, with W-based hard particles immersed in a matrix. It is the only known hardfacing alloy which possesses this type of microstructure while simultaneously avoiding the long, needle-like particles known to cause problematic embrittlement in chromium carbide overlays and many nanostructured steel alloys.

WHY VECALLOY 752 OUTPERFORMS WC-Ni PTA 1.

Homogeneity: Unlike a PTA coating which effectively involves depositing two separate materials simultaneously, a Ni matrix and WC particles, Vecalloy 752 is deposited as a single alloy which naturally grows a network of carbide and boride fine-scale precipitates. Whereas WC may sink or float in a molten weld pool resulting in varied performance through the thickness of the weld, the Vecalloy 752 carbide and boride network are thermodynamically driven to precipitate at equal concentrations throughout the weld thickness.

2.

Consistent Performance: Because the tungsten boride particles form throughout the weld thickness regardless of parameter variations, Vecalloy 752 will deliver consistent performance. It is common practice when wear testing WC/Ni PTA coatings to perform two ASTM G65 tests simultaneously on one coating: 1) to remove the soft Ni layer, and 2) to test the performance of the WC rich coating. This testing technique is not necessary in Vecalloy 752. The coating will exhibit a high level of consistent performance from the surface down to the coating substrate interface. The coating performance of WC/Ni PTA is highly dependent on the welding technique of a skilled operator and varies greatly; the coating performance of Vecalloy 752 is thermodynamically driven towards consistent high performance.

3.

Fine-Scale Microstructure: WC PTA coatings typically use carbide particles on the order of 50 to 200 microns in size. Unlike typical WC PTA applications, the carbides and borides in Vecalloy 752 are thermodynamically grown in the liquid alloy and thus are always consistent in size, shape and distribution. This fine scale microstructure has many beneficial effects such as preventing small sand particles from attacking the matrix directly, and distributing thermal stresses more evenly upon cooling. However, perhaps the most important benefit of the Vecalloy 752 microstructure is the ability to withstand impact and high stresses. Almost every application which is commonly understood to be an abrasive environment is also an environment containing high stress and significant levels of impact.

For additional and more detailed technical information please contact: SCOPERTA at [email protected]

11760 Sorrento Valley Road, Suite D, San Diego CA 92121 USA Phone (858) 704-4013 Fax (858) 704-4014

Justin Cheney, PH. D [email protected]

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T EC HNI CA L DATA SH E E T

In the micrograph (right) the WC particles are clumped together in some areas of the weld and some sections are free of WC particles in the WCNi PTA coating. Whereas, the carbide spacing is thermodynamically driven to a very precise spacing in the Vecalloy 752 weld.

Carbide Depleted

Carbide Rich

Notice too, large cracks (highlighted by the white arrow) running through the microstructure of the 25X WC PTA coating. Crack Large carbides can be seen below in the WC PTA micrograph, but at 500X the hard-phases in Vecalloy 752 are very small.

WC PTA at 25X

WC PTA at 500X

Vecalloy 752 at 500X

For additional and more detailed technical information please contact: SCOPERTA at [email protected]

11760 Sorrento Valley Road, Suite D, San Diego CA 92121 USA Phone (858) 704-4013 Fax (858) 704-4014

Justin Cheney, PH. D [email protected]

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T EC HNI CA L DATA SH E E T

HOW VECALLOY 752 OUTPERFORMS WC-Ni PTA Many people are surprised to see that despite Vecalloy 752’s nearly equal wear resistance compared to WC PTA coatings, Vecalloy 752 significantly outlasts WC PTA in actual applications. The reason lies in the revolutionary improvement in impact resistance. While WC PTA is well known as the standard for abrasion resistance under ASTM G65 testing, relatively low levels of impact can generate cracks and significant levels of material loss. As shown in the diagram below, when subjected to 30 minutes of wear (ASTM G65) Vecalloy 752 c o m p e t e s c l o s e l y w i t h W C / N i P TA a n d outperforms chrome carbide and nanostructured hard facing.

How can we define the level of impact that one should pay attention to? This particular impact test is standardized to 20J of impact energy, the amount of energy developed by dropping a 2kg rock a distance of 1m. It stands to reason that many more applications should consider the use of coating solutions with better impact resistance.

When subjected to repeated 20J impacts, Vecalloy 752 lasts 4X as long as the most impact-resistant chrome carbide and 30X as long as WC/Ni PTA.

For additional and more detailed technical information please contact: SCOPERTA at [email protected]

11760 Sorrento Valley Road, Suite D, San Diego CA 92121 USA Phone (858) 704-4013 Fax (858) 704-4014

Justin Cheney, PH. D [email protected]

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T EC HNI CA L DATA SH E E T

VECALLOY 752 PTA COST, PROCESS, AND PRODUCTIVITY ADVANTAGES Vecalloy 752 delivers WC/Ni PTA performance with the cost and productivity advantages of iron-based alloys and MIG (GMAW) welding. The material properties of Vecalloy 752 allow for unique advantages in cost, process and productivity that expand the use of extremely abrasion resistant materials into wider markets. Vecalloy 752 is an iron-based alloy resulting in significant material cost savings compared to WCNi products. Further, MIG welded Vecalloy 752

has a ~99% deposit efficiency while WC/Ni PTA has a 70% deposit efficiency. This means that 1.4kg of WC/Ni must be purchased for 1kg deposited. Vecalloy 752, because it is iron-based, has a lower density than WC/Ni. This results in further cost savings.

Consider the manufacture of a 12” x 12” (300mm x 300mm) wear plate with a 1/4” (6mm) overlay. In production this plate would require half the amount of material by weight when using Vecalloy 752 as opposed to WC PTA. This immediately results in significant cost savings, in addition to significantly reducing the weight of the component. Unlike WC/Ni, which is typically deposited using PTA because MIG results in an even less uniform structure and poor performance, Vecalloy 752 has no loss in performance when MIG welded. This allows MIG equipment and processes to be used instead of PTA. MIG equipment avoids the

frequent powder clogging of PTA process and is cheaper to purchase, maintain, and run. In addition to direct material cost, Vecalloy 752 can be deposited with far higher productivity than WC/Ni PTA.

For example, WC/Ni PTA is typically deposited at a rate of 11 in3/hr. Vecalloy 752 is typically deposited at a rate greater than 40 in3/hr, 4 times as fast!

For additional and more detailed technical information please contact: SCOPERTA at [email protected]

11760 Sorrento Valley Road, Suite D, San Diego CA 92121 USA Phone (858) 704-4013 Fax (858) 704-4014

Justin Cheney, PH. D [email protected]

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T EC HNI CA L DATA SH E E T

SUGGESTED APPLICATIONS Vecalloy 752 coatings are suggested for use in any applications where wear resistance is required. The revolutionary improvement in impact resistance and toughness will typically result in an extended lifetime over WC PTA and Chromium Carbide coatings. Specific applications include: ‣ ‣ ‣ ‣ ‣

Shaker Screens Grader Blades and other Ground Engaging Tools Chute Blocks Pipe I.D. Wear Plate

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Mill Liners Slurry Pipe Shovel Wear Packages Other Mining Applications

HOW TO USE VECALLOY 752 Vecalloy 752 is currently available in 1/16” metal cored wire. Additional welding wire diameters are available upon request. The suggested spray parameters and expected results are provided below.

Vecalloy 752 1/16-inch GMAW WELDING PARAMETERS Wire Diameter

1/16 in (1.6 mm)

Current

DCEP

Desired Weld Thickness

6 - 8 mm

Voltage

28 - 30

Amperage

250 - 280

Shielding Gas

Ar 100%, Ar 98%/O2 2%

Stickout

1 in (25 - 32 mm)

Preheat

300 - 400F (150 - 200C)

Torch Drag Angle

5 - 15°

Travel Speed

3 - 5 in/min

Expected Hardness

65 - 70 HRc

Expected ASTM G65 mass loss

0.06 - 0.08 g

For application specific guidance on proper welding procedures please contact: Cameron Eibl at [email protected]

11760 Sorrento Valley Road, Suite D, San Diego CA 92121 USA Phone (858) 704-4013 Fax (858) 704-4014

Justin Cheney, PH. D [email protected]

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