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RP Graphite Electrode D450-500

Grade

D450-500 = φ450–500 mm

Large ordinary-power EAF and calcium-carbide/silicon furnaces; slightly lower strength and higher resistivity from larger billet size.

Standard cost $$

Values for the D450-500 condition

Other RP Graphite Electrode tempers and conditions

RP Graphite Electrode is listed in 5 conditions; see the grade overview at RP Graphite Electrode.

Compare all 5 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
Φ550–600 mm
Big submerged-arc furnaces (FeSi, CaC₂, FeMn) where cross-section, not current density, carries the load.—60.228 HV125 W/m·K
D450-500This page
Φ450–500 mm
Large ordinary-power EAF and calcium-carbide/silicon furnaces; slightly lower strength and higher resistivity from larger billet size.—70.2230 HV130 W/m·K
D350-400Default
Φ350–400 mm
The workhorse RP size for ordinary-power EAF, LF and submerged-arc ferroalloy furnaces.—70.2532 HV140 W/m·K
Φ200–300 mm
Small ladle furnaces, ferroalloy and foundry furnaces; best resistivity and strength of the RP family.—80.335 HV150 W/m·K
Nipple / connecting pin stock
Denser, higher-strength graphite used for the tapered connecting pin so the joint outlives the electrode body.—12——170 W/m·K

What is RP Graphite Electrode D450-500?

RP Graphite Electrode D450-500 is RP Graphite Electrode in the D450-500 grade — large ordinary-power EAF and calcium-carbide/silicon furnaces; slightly lower strength and higher resistivity from larger billet size. RP Graphite Electrode D450-500 has a tensile strength of 7 MPa (0.943 ksi), weaker than 95% of ceramic grades. Elongation at break is 0.22% and the elastic modulus is 9.3 GPa (1.35 Msi). RP Graphite Electrode D450-500 has a density of 1.55 g/cm³ (0.056 lb/in³), lighter than 96% of ceramic grades. It melts at 3,650°C (6,602 °F). D350-400 is the default condition FabDigit quotes; D450-500 is available on request or by drawing note.

Advantages

  • Lightweight — 1.55 g/cm³ (0.056 lb/in³), better than 96% of ceramic grades
  • Easy to machine — 90/100, better than 94% of ceramic grades
  • Conducts heat well — 130 W/m·K (75.1 BTU/hr·ft·°F), better than 91% of ceramic grades
  • Ductile — tolerates forming and impact — 0.22%, better than 85% of ceramic grades

Limitations

  • Hard to polish — 25/100, worse than 97% of ceramic grades
  • Low stiffness — 9.3 GPa (1.35 Msi), worse than 94% of ceramic grades
  • Low fracture toughness — 0.95 MPa·√m (0.865 ksi·√in), worse than 93% of ceramic grades
  • Limited service temperature — 450°C (842 °F), worse than 77% of ceramic grades

RP Graphite Electrode D450-500 properties

Typical room-temperature values for RP Graphite Electrode D450-500; 15 are specific to this condition. Other listed values are RP Graphite Electrode reference data and may not represent this condition. Bars are the position among ceramic grades.

Physical3

RP Graphite Electrode D450-500 has a density of 1.55 g/cm³ (0.056 lb/in³), lighter than 96% of ceramic grades. It melts at 3,650°C (6,602 °F).

Density1.55 g/cm³0.06 lb/in³
Melting Point (Solidus)3,650°C6,602 °F
Porosity25%

Mechanical11

RP Graphite Electrode D450-500 has a tensile strength of 7 MPa (0.943 ksi), weaker than 95% of ceramic grades. Elongation at break is 0.22% and the elastic modulus is 9.3 GPa (1.35 Msi).

Elastic (Young's) Modulus9.3 GPa1.3 Msi
Shear Modulus3.8 GPa0.55 Msi
Poisson's Ratio0.15
Tensile Strength (Ultimate)7 MPa0.94 ksi
Elongation at Break0.22%
Compressive Strength21 MPa3 ksi
Flexural Strength10 MPa1.4 ksi
Shear Strength6 MPa0.8 ksi
Fracture Toughness (K_IC)0.95 MPa·√m0.86 ksi·√in
Hardness, Vickers30 HV
Hardness, Mohs1.5

Thermal5

RP Graphite Electrode D450-500 is rated for continuous service to 450°C (842 °F). It conducts heat at 130 W/m·K (75.1 BTU/hr·ft·°F), better than 91% of ceramic grades. Thermal expansion is 2.2 µm/m·K (1.22 µin/in·°F).

Thermal Conductivity130 W/m·K75.1 BTU/hr·ft·°F
Specific Heat Capacity710 J/kg·K0.17 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)2.2 µm/m·K1.2 µin/in·°F
Max Service Temperature (continuous)450°C842 °F
Min Service Temperature-200°C-328 °F

Electrical2

RP Graphite Electrode D450-500 has an electrical resistivity of 8.5×10⁻⁶ Ω·m.

Electrical Resistivity8.5×10⁻⁶ Ω·m335 µΩ·in
Volume Resistivity8.5×10⁻⁴ Ω·cm

Chemical & Environmental2

Corrosion resistance is good (64/100), worse than 69% of ceramic grades.

Corrosion ResistanceGood64/100
Chemical Resistance SummaryInert to nearly all mineral acids, alkalis, salts, molten non-oxidizing metals and slags; attacked by strong oxidizers (hot concentrated HNO₃, H₂SO₄, chromic acid, molten alkali nitrates), and oxidizes progressively in air, CO₂ or steam above ~400–500 °C.

Sustainability4

Producing a kilogram of RP Graphite Electrode D450-500 takes about 65 MJ of energy and emits 6 kg of CO₂ — less than 74% of ceramic grades. Typical recycled content is 5%.

Embodied Energy (primary production)65 MJ/kg27,945 BTU/lb
Embodied Carbon (primary production)6 kg CO₂/kg
Embodied Water25 L/kg3 gal/lb
Typical Recycled Content5%

Manufacturability3

RP Graphite Electrode D450-500's machinability is excellent (90/100, better than 94% of ceramic grades).

MachinabilityExcellent90/100
PolishabilityPoor25/100
Sintering / Firing Temperature2,900°C5,252 °F

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

Working with RP Graphite Electrode D450-500

Is RP Graphite Electrode easy to machine?

Machines very easily dry with sharp carbide or PCD tooling at high speed and zero coolant; mandatory dust extraction, and support the part because edges chip.

Can RP Graphite Electrode be welded?

Not weldable — sections are joined only by machined tapered threaded nipples with graphite cement, or bonded with carbon/furan cements.

Can RP Graphite Electrode be formed, bent or molded?

Made by extruding a hot coke/pitch paste, multi-stage baking to ~1000 °C, optional pitch impregnation, then graphitization at 2800–3000 °C; no post-forming of the finished rod.

What surface finishes work on RP Graphite Electrode?

Turned to size and socket-threaded (3TPI/4TPI); optional anti-oxidation aluminium/SiC coating or ceramic paint on the column, and sealed sockets to keep out moisture.

RP Graphite Electrode 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
ashGB/T 3079 limit ≤0.5 %; Si, Fe, Al, Ca oxides≤ 0.50.3
Sresidual sulfur from petroleum coke; drives puffing control≤ 0.250.12
volatile matterafter graphitization≤ 0.20.05
Cfixed carbon after graphitization; petroleum coke + coal-tar pitch binder≥ 99 (balance)—

RP Graphite Electrode D450-500 — frequently asked

What is RP Graphite Electrode D450-500 used for?

RP Graphite Electrode D450-500 is typically used for low-power arc furnaces, ferroalloy smelting and resistor elements. In short: most economical electrode grade; petroleum-coke regular-power class; lowest current density rating.

What is the tensile strength of RP Graphite Electrode D450-500?

RP Graphite Electrode D450-500 has a typical tensile strength of 7 MPa (0.943 ksi) — weaker than 95% of ceramic grades. Strength varies by condition: see the 5 listed tempers.

Is RP Graphite Electrode D450-500 easy to machine?

Yes — machinability is rated excellent (90/100, better than 94% of ceramic grades). Machines very easily dry with sharp carbide or PCD tooling at high speed and zero coolant; mandatory dust extraction, and support the part because edges chip.

Can RP Graphite Electrode D450-500 be welded?

Not weldable — sections are joined only by machined tapered threaded nipples with graphite cement, or bonded with carbon/furan cements.

What surface finishes work on RP Graphite Electrode D450-500?

Turned to size and socket-threaded (3TPI/4TPI); optional anti-oxidation aluminium/SiC coating or ceramic paint on the column, and sealed sockets to keep out moisture.

Can RP Graphite Electrode D450-500 be formed, bent or molded?

Made by extruding a hot coke/pitch paste, multi-stage baking to ~1000 °C, optional pitch impregnation, then graphitization at 2800–3000 °C; no post-forming of the finished rod.

What is the maximum service temperature of RP Graphite Electrode D450-500?

RP Graphite Electrode D450-500 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. GB/T 3079 (2008)
  2. JIS R7601 Testing methods for carbon and graphite materials — JISC (2012)
  3. ASM Engineered Materials Handbook Vol.4 — Ceramics and Glasses (carbon/graphite section) — ASM International (1991)
  4. Graphite electrode RP/HP/UHP property tables (2024)

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.