VECALLOY 752 is an iron-based alloy designed for aggressive environments involving impact, abrasion, and erosion. It grows extremely hard tungsten boride particles throughout the weld bead that provide wear resistance similar to WC-Ni overlays at a lower cost. The small particle size also provides much higher impact resistance than other hardfacing products. It can be deposited using MIG welding at a lower cost and higher productivity compared to WC-Ni PTA coatings.

1. VECALLOY 752 has been specifically designed to perform in ag-
gressive environments where impact, abrasive wear, and ero-
sive wsear are factors. VECALLOY 752 is an iron-based alloy
which grows extremely hard, near spherical, tungsten boride
particles throughout the entire weld bead thickness. In terms of
wear resistance, the high density of tungsten boride particles
enable performance on a level similar to WC-Ni overlays at a
lower price point. Further, the small scale of a tungsten boride
particles provides enhanced impact resistance, 4-30X that of
conventional hardfacing products, including WC-based, CCO
(chrome carbide overlays), and nanostructure forming steels.
DESIGN APPROACH
The design process for VECALLOY 752 involves a proprietary high throughput computational metallurgical process to evalu-
ate millions of candidates alloy compositions. Potential candidates are evaluated using advanced screening processes al-
lowing for thorough and rapid development of materials.
VECALLOY 752
Technical Datasheet
PRODUCT OVERVIEW
VECALLOY 752 PERFORMANCE
Overlay Properties
 Hardness 66-70 HRC
 ASTM G65A: 0.06-0.08 grams lost (low stress abrasion
 Coefficient of Friction <0.09
(ASTM G77 in Mineral Oil)
 Impact Resistance: >6,000 20J Impacts
to Failure
 Hard Boride/Carbide Fraction: >50%
10073 Commerce Park Drive. Cincinnati, OH 45246 / Phone: 513-847-3586 / Fax: 513-847-2880
E-Mail: sales@polymet.us
Vecalloy 752
at
1,000X
~2600HV Complex Tungsten
Boride Particles, Harder than
Tungsten Carbide
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 a microstructure which looks similar to WC/Ni PTA, W-based
hard particles immersed in a matrix. It is the only hardfacing alloy which possesses this type of microstructure while simultane-
ously avoiding the long needle-like particles known to cause problematic embrittlement in chromium carbide overlays and many
nanostructured steel alloys.

2. VECALLOY 752
Technical Datasheet
752
WHY VECALLOY 752 OUTPERFORMS WC-NI PTA
2. Fine-Scale Microstructure: WC PTA coatings typically use carbide particles on the order of 50 to 200 microns in
size. Notice how large carbides can be seen in the WC PTA micrograph, but at 500X the hard-phases in 752 are
very small. 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 microstruc-
ture 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 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.
Carbide
Crack
WC PTA
at
25X
Carbide
Depleted
WC PTA
at
500 X
VECALLOY
752 at
500 X
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 a varied perfor-
mance through the thickness of the weld, the VECALLOY 752 carbide and boride network are thermodynamically driv-
en to precipitate at equal concentrations throughout the weld thickness. Notice in the micrographs below how the
WC particles are clumped together in some areas of the weld and some sections are free of WC particles in the WC-Ni
PTA coating. Whereas, the carbide spacing is thermodynamically driven to a very precise spacing in the VECALLOY 752
weld.
WHY VECALLOY 752 OUTPERFORMS WC-NI PTA AND CHROMIUM CARBIDE
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 application. The answer lies in the revolutionary improvement in im-
pact resistance. Notice large cracks (highlighted by white arrows) running through the microstructure of the 25X WC PTA
coating. 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 repeat-
ed 20J impacts, VECALLOY 752 lasts 4x as long as the most impact resistant chrome carbide and 30X as long as WC/Ni PTA.
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.

3. VECALLOY 752 COST, PROCESS, AND PRODUCTIVITY ADVANTAGES
VECALLOY 752 deliver 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 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 WC-Ni products. Further, MIG welded VECALLOY 752 has a ~99% deposit efficiency while WC/Ni PTA has a 70% de-
posit efficiency. This means that 1.4kg of WC/Ni must be purchased for every 1kg deposited.
VECALLOY 752, because it is iron based, has a lower density than WC/Ni this results in further cost savings. Consider the manufac-
turing 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 sav-
ings, in addition to significantly reducing the weight of the component.
Unlike WC/Ni, which is typically deposited using PTA because MIG results in a non-uniform structure and poor performance, VE-
CALLOY 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 in2
/hr. VECALLOY 752 is typically deposited at a rate of 40 in3
/hr, almost 4
times as fast!
VECALLOY 752
Technical Datasheet

4. SUGGESTED APPLICATIONS
VECALLOY 752 coatings are suggested for use in any application where wear resistance is required. The revolutionary im-
provement in impact resistance and toughness will typically result in an extended lifetime over WC PTA and Chromium Car-
bide coatings. Specific applications include:
 Shaker Screens
 Grade Blades and other Ground Engaging Tools
 Chute Blocks
 Pipe I.D.
 Wear Plate
 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 diameters are available upon request. The
suggested welding parameters and expected results are provided based on the following pages.
For application specific guidance on proper welding procedures please contact: sales@polymet.us
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 mm)
Preheat 300—400 F (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
VECALLOY 752 1/16 INCH GMAW WELDING PARAMETERS
VECALLOY 752
Technical Datasheet