Tungsten Alloy Rod in Blank Form: 90% W and 93% W Heavy Alloy Properties and Machining

Tungsten Alloy Rod Supplied in Blank Form

Blank-form tungsten alloy rod is supplied as a near-net bar that has not yet been finished to final drawing, so the buyer can machine, grind or cut it to the required geometry instead of paying for finishing work that will be removed later. Tungsten heavy alloys pair a very high density with useful strength, stiffness and thermal stability, which makes them the material of choice wherever a large mass has to be concentrated into a small volume. Typical duties include counterweights, radiation shielding, kinetic energy components, vibration damping masses and tooling inserts, and the blank form keeps the cost of the raw shape low while leaving the final tolerances in the buyer's hands.

Properties of 90% W Tungsten Alloy Bar

The 90 percent tungsten grade is the general purpose heavy alloy. It offers the highest elongation and the highest electrical conductivity of the two grades below, and it is the easier of the two to machine.

Property	Value
Tungsten content	90% W
Density	17 g/cc
Density	0.614 lb/cu in
Proportional elastic limit	45,000 PSI
Ultimate tensile strength	110,000 PSI
Yield strength, 0.2% offset	90,000 PSI
Elongation	8% in 1 in
Hardness	24 HRC
Modulus of elasticity	40 x 10^6 PSI
Electrical conductivity	14% IACS
Thermal conductivity	0.23 CGS units
Coefficient of thermal expansion	5.4 x 10^-6 per deg C at 20 to 400 deg C

Properties of 93% W Tungsten Alloy Bar

The 93 percent tungsten grade trades a little ductility and conductivity for a higher density, a higher elastic limit and a harder surface. It suits parts where mass and stiffness are the governing requirements.

Property	Value
Tungsten content	93% W
Density	17.7 g/cc
Density	0.639 lb/cu in
Proportional elastic limit	60,000 PSI
Ultimate tensile strength	130,000 PSI
Yield strength, 0.2% offset	90,000 PSI
Elongation	10% in 1 in
Hardness	30 HRC
Modulus of elasticity	53 x 10^6 PSI
Electrical conductivity	14% IACS
Thermal conductivity	0.27 CGS units
Coefficient of thermal expansion	4.5 x 10^-6 per deg C at 20 to 400 deg C

Reading the two tables side by side shows the shape of the trade off. Moving from 90 percent to 93 percent tungsten raises density from 17 to 17.7 g/cc, the proportional elastic limit from 45,000 to 60,000 PSI, ultimate tensile strength from 110,000 to 130,000 PSI and hardness from 24 to 30 HRC, while the coefficient of thermal expansion falls from 5.4 to 4.5. The lower expansion figure is often the deciding factor in instrumentation and shielding work, where dimensional stability across a wide temperature range matters as much as mass.

Why Blank Form Is Preferred for Machining

Tungsten heavy alloy is difficult and expensive to machine, so the amount of material that has to be removed drives the cost of a finished part. Blank-form rod is supplied close to the size that will be machined, which reduces cutting time, tool wear and scrap losses, and it allows the buyer to apply the finishing tolerances required by the end application. In pressing and extrusion tooling the same characteristics matter for a different reason: a rod that resists impact and cracking while presenting a stable, hard surface reduces press downtime and picks up less extruded metal, so the tooling runs for longer between maintenance stops. The material also resists corrosion in service, which keeps a heavy alloy component dimensionally stable in damp or chemically active environments.

Selection Guidance for Heavy Alloy Rod

Choose 90% W where a slightly lower mass and easier machining are preferred, and 93% W where the highest density and stiffness are needed.

Confirm the required diameter, length and machining allowance before ordering, since blank sizes are planned around the finished part.

State the maximum service temperature so the applicable expansion and strength data can be checked.

Declare whether the part will be machined, ground or wire cut, because each process prefers a different blank condition.

For shielding duty, check the shielding calculation against the density of the grade selected.

Ask for the certified property values for the delivered lot rather than relying on typical figures.

Tungsten heavy alloys of this family, in which the tungsten grains are bonded by a ductile nickel-iron or nickel-copper matrix, are generally specified against the recognised specification family for tungsten base high density metal, which defines the composition and the mechanical property limits for each class. Buyers who need traceability for shielding or aerospace work should confirm the class and the certified values when the order is placed.

Frequently Asked Questions

Q: What does blank form mean for a tungsten alloy rod?
It means the rod is supplied as a near-net bar that has been formed but not finished to final drawing, so the buyer machines or grinds it to the required shape and tolerance instead of paying for finishing that would be cut away.

Q: What is the density of the 90% W and 93% W grades?
The 90 percent tungsten grade is 17 g/cc, equal to 0.614 lb/cu in, and the 93 percent tungsten grade is 17.7 g/cc, equal to 0.639 lb/cu in.

Q: How do the two grades differ in strength and hardness?
Ultimate tensile strength rises from 110,000 PSI at 90 percent tungsten to 130,000 PSI at 93 percent tungsten, the proportional elastic limit rises from 45,000 to 60,000 PSI, and hardness rises from 24 to 30 HRC.

Q: Why are tungsten alloy products used for tooling and extrusion work?
Because the material combines high density, high temperature resistance, impact and crack resistance, and corrosion resistance, it holds its shape under load and reduces press downtime while picking up less extruded metal.

Q: Can the rod be machined to a customer drawing?
Yes. Blank rod can be supplied as formed and then machined, ground or cut to the customer's drawing, and the machining allowance should be agreed before the blank size is fixed.

Q: Which applications suit heavy alloy rod best?
Counterweights, radiation shielding, vibration damping masses, kinetic energy components and tooling inserts are the classic applications, because each of them needs a large mass packed into the smallest possible volume.