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Isostatic Graphite UFG-5

Grade

UFG-5 = ultra-fine grain (~5 µm) EDM electrode grade

Pick the ultra-fine-grain (~5 µm) grade as the mainstream EDM electrode material for stable discharge, low electrode wear and moderately fine rib detail.

High cost $$$$

Values for the UFG-5 condition

Other Isostatic Graphite tempers and conditions

Isostatic Graphite is listed in 4 conditions; see the grade overview at Isostatic Graphite.

Compare all 4 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
FG-10Default
Fine grain (~10–20 µm), general-purpose isostatic graphite
Use the fine-grain (~10–20 µm) general-purpose grade as the cost-effective choice for roughing EDM electrodes, continuous-casting moulds, heating elements and general hot-zone parts.—27——105 W/m·K
Halogen-purified high-purity grade
Use the halogen-purified grade (ash < 5 ppm) for monocrystalline silicon and sapphire hot zones, crucibles, epitaxy and semiconductor fixtures where metal contamination is prohibited.—27——120 W/m·K
UFG-5This page
Ultra-fine grain (~5 µm) EDM electrode grade
Pick the ultra-fine-grain (~5 µm) grade as the mainstream EDM electrode material for stable discharge, low electrode wear and moderately fine rib detail.—35——90 W/m·K
Superfine grain (≤2 µm), high-density precision grade
Choose the superfine-grain (≤2 µm) high-density grade for mirror-finish and micro EDM electrodes, optical moulds and fine structures needing 55 MPa tensile strength and the finest discharge texture.—55——70 W/m·K

What is Isostatic Graphite UFG-5?

Isostatic Graphite UFG-5 is Isostatic Graphite in the UFG-5 grade — pick the ultra-fine-grain (~5 µm) grade as the mainstream EDM electrode material for stable discharge, low electrode wear and moderately fine rib detail. Isostatic Graphite UFG-5 has a tensile strength of 35 MPa (5.08 ksi), weaker than 71% of ceramic grades. The elastic modulus is 12.5 GPa (1.81 Msi). Isostatic Graphite UFG-5 has a density of 1.81 g/cm³ (0.0654 lb/in³), lighter than 88% of ceramic grades. It melts at 3,650°C (6,602 °F). FG-10 is the default condition FabDigit quotes; UFG-5 is available on request or by drawing note.

Advantages

  • Easy to machine — 85/100, better than 91% of ceramic grades
  • Lightweight — 1.81 g/cm³ (0.0654 lb/in³), better than 88% of ceramic grades
  • Conducts heat well — 90 W/m·K (52 BTU/hr·ft·°F), better than 82% of ceramic grades

Limitations

  • Low stiffness — 12.5 GPa (1.81 Msi), worse than 88% of ceramic grades
  • Hard to polish — 55/100, worse than 85% of ceramic grades
  • Limited service temperature — 450°C (842 °F), worse than 77% of ceramic grades

Isostatic Graphite UFG-5 properties

Typical room-temperature values for Isostatic Graphite UFG-5; 15 are specific to this condition. Other listed values are Isostatic Graphite reference data and may not represent this condition. Bars are the position among ceramic grades.

Physical3

Isostatic Graphite UFG-5 has a density of 1.81 g/cm³ (0.0654 lb/in³), lighter than 88% of ceramic grades. It melts at 3,650°C (6,602 °F).

Density1.81 g/cm³0.07 lb/in³
Melting Point (Solidus)3,650°C6,602 °F
Porosity11%

Mechanical10

Isostatic Graphite UFG-5 has a tensile strength of 35 MPa (5.08 ksi), weaker than 71% of ceramic grades. The elastic modulus is 12.5 GPa (1.81 Msi).

Elastic (Young's) Modulus12.5 GPa1.8 Msi
Shear Modulus4.6 GPa0.67 Msi
Bulk Modulus6 GPa0.88 Msi
Poisson's Ratio0.17
Tensile Strength (Ultimate)35 MPa5.1 ksi
Compressive Strength110 MPa16 ksi
Flexural Strength55 MPa8 ksi
Shear Strength33 MPa4.8 ksi
Fracture Toughness (K_IC)1.1 MPa·√m1 ksi·√in
Hardness, Mohs1.5

Thermal5

Isostatic Graphite UFG-5 is rated for continuous service to 450°C (842 °F). It conducts heat at 90 W/m·K (52 BTU/hr·ft·°F), better than 82% of ceramic grades. Thermal expansion is 4.8 µm/m·K (2.67 µin/in·°F).

Thermal Conductivity90 W/m·K52 BTU/hr·ft·°F
Specific Heat Capacity710 J/kg·K0.17 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)4.8 µm/m·K2.7 µin/in·°F
Max Service Temperature (continuous)450°C842 °F
Min Service Temperature-269°C-452 °F

Electrical2

Isostatic Graphite UFG-5 has an electrical resistivity of 1.3×10⁻⁵ Ω·m.

Electrical Resistivity1.3×10⁻⁵ Ω·m512 µΩ·in
Volume Resistivity0 Ω·cm

Chemical & Environmental2

Corrosion resistance is very good (75/100), better than 50% of ceramic grades.

Corrosion ResistanceVery good75/100
Chemical Resistance Summary—

Sustainability4

Producing a kilogram of Isostatic Graphite UFG-5 takes about 190 MJ of energy and emits 16 kg of CO₂ — more than 62% of ceramic grades. Typical recycled content is 5%.

Embodied Energy (primary production)190 MJ/kg81,685 BTU/lb
Embodied Carbon (primary production)16 kg CO₂/kg
Embodied Water60 L/kg7.2 gal/lb
Typical Recycled Content5%

Manufacturability3

Isostatic Graphite UFG-5's machinability is excellent (85/100, better than 91% of ceramic grades).

MachinabilityExcellent85/100
PolishabilityGood55/100
Sintering / Firing Temperature2,800°C5,072 °F

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with Isostatic Graphite UFG-5

Is Isostatic Graphite easy to machine?

Cut dry with no coolant, using carbide or PCD tooling at high spindle speed and light feed. Explosion-rated vacuum dust extraction is required, and exit edges should be chamfered to prevent break-out.

Can Isostatic Graphite be welded?

Not weldable; assemblies are made with graphite threaded joints, graphite tenon joints, or carbon cement with a carbonising binder.

Can Isostatic Graphite be formed, bent or molded?

Shaped only by machining or wire EDM from pressed and graphitised blanks; no plastic forming is possible. Large parts must be nested to the available blank sizes.

What surface finishes work on Isostatic Graphite?

Grind to final size and ultrasonically clean to remove residual dust. For oxidation resistance apply SiC, pyrolytic-carbon or CVD coatings, or phosphate impregnation; high-purity applications require halogen-atmosphere purification.

Isostatic Graphite chemical composition (wt %)

Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.

ElementSpec limit (wt %)Nominal
ashstandard grade ash ≤500–1000 ppm; halogen-purified <5 ppm (HP-5N)5×10⁻⁴ – 0.10.03
Sresidual sulfur, very low after graphitization≤ 0.030.01
Femain metallic ash impurity; <1 ppm in purified grades≤ 0.010
Cfixed carbon; needle/pitch coke + pitch binder, 2800–3000 °C≥ 99.9 (balance)—

Isostatic Graphite UFG-5 — frequently asked

What is Isostatic Graphite UFG-5 used for?

Isostatic Graphite UFG-5 is typically used for EDM electrodes, hot-press molds, semiconductor fixtures and continuous casting dies. In short: finest-grain isotropic graphite; strongest common graphite grade; 5N purity available.

What is the tensile strength of Isostatic Graphite UFG-5?

Isostatic Graphite UFG-5 has a typical tensile strength of 35 MPa (5.08 ksi) — weaker than 71% of ceramic grades. Strength varies by condition: see the 4 listed tempers.

Is Isostatic Graphite UFG-5 easy to machine?

Yes — machinability is rated excellent (85/100, better than 91% of ceramic grades). Cut dry with no coolant, using carbide or PCD tooling at high spindle speed and light feed. Explosion-rated vacuum dust extraction is required, and exit edges should be chamfered to prevent break-out.

Can Isostatic Graphite UFG-5 be welded?

Not weldable; assemblies are made with graphite threaded joints, graphite tenon joints, or carbon cement with a carbonising binder.

What surface finishes work on Isostatic Graphite UFG-5?

Grind to final size and ultrasonically clean to remove residual dust. For oxidation resistance apply SiC, pyrolytic-carbon or CVD coatings, or phosphate impregnation; high-purity applications require halogen-atmosphere purification.

Can Isostatic Graphite UFG-5 be formed, bent or molded?

Shaped only by machining or wire EDM from pressed and graphitised blanks; no plastic forming is possible. Large parts must be nested to the available blank sizes.

What is the maximum service temperature of Isostatic Graphite UFG-5?

Isostatic Graphite UFG-5 is rated for continuous use to about 450°C (842 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Sources

  1. ASTM C709 — Standard Terminology Relating to Manufactured Carbon and Graphite — ASTM (2021)
  2. ASTM C651 / C695 / C749 — Flexural, Compressive and Tensile Testing of Graphite — ASTM (2020)
  3. IG-11 / IG-43 / IG-56 Isotropic Graphite Property Sheets — Toyo Tanso (2022)
  4. SIGRAFINE isostatic graphite grades (R6650, R6710) — SGL Carbon (2022)
  5. Properties and Characteristics of Graphite (EDM-3, EDM-AF5) — POCO Graphite / Entegris (2015)
  6. ASM Engineered Materials Handbook Vol. 4 — Ceramics and Glasses (carbon & graphite) — ASM International (1991)

Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.