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Sialon AB (As built (as printed))

Print state

Pick when hardness and hot wear resistance dominate — inserts for turning/milling nickel superalloys and grey cast iron at high speed.

High cost $$$$

Values for the AB condition

Other Sialon tempers and conditions

Sialon is listed in 3 conditions; see the grade overview at Sialon.

Compare all 3 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
General-purpose sintered sialon
Lower-cost, slightly less dense grade for wear plates, nozzles and molten-metal handling where peak strength is not required.———1,350 HV16 W/m·K
BETADefault
Β-Sialon
Default structural grade: best balance of strength, toughness and thermal shock for thermocouple sheaths, weld pins, riser tubes and pump parts.———1,550 HV21 W/m·K
ABThis page
As built (as printed)
Pick when hardness and hot wear resistance dominate — inserts for turning/milling nickel superalloys and grey cast iron at high speed.———1,800 HV20 W/m·K

What is Sialon AB?

Sialon AB is Sialon in the AB condition — pick when hardness and hot wear resistance dominate — inserts for turning/milling nickel superalloys and grey cast iron at high speed. Sialon AB has a tensile strength of 350 MPa (50.8 ksi), stronger than 71% of ceramic grades. The elastic modulus is 300 GPa (43.5 Msi). Sialon AB has a density of 3.25 g/cm³ (0.117 lb/in³), lighter than 70% of ceramic grades. It melts at 1,800°C (3,272 °F). BETA is the default condition FabDigit quotes; AB is available on request or by drawing note.

Advantages

  • Good corrosion resistance — 92/100, better than 88% of ceramic grades
  • High service temperature — 1,300°C (2,372 °F), better than 77% of ceramic grades

Sialon AB properties

Typical room-temperature values for Sialon AB; 11 are specific to this condition. Other listed values are Sialon reference data and may not represent this condition. Bars are the position among ceramic grades.

Physical3

Sialon AB has a density of 3.25 g/cm³ (0.117 lb/in³), lighter than 70% of ceramic grades. It melts at 1,800°C (3,272 °F).

Density3.25 g/cm³0.12 lb/in³
Melting Point (Solidus)1,800°C3,272 °F
Porosity0.3%

Mechanical11

Sialon AB has a tensile strength of 350 MPa (50.8 ksi), stronger than 71% of ceramic grades. The elastic modulus is 300 GPa (43.5 Msi).

Elastic (Young's) Modulus300 GPa43.5 Msi
Shear Modulus113 GPa16.4 Msi
Bulk Modulus205 GPa29.7 Msi
Poisson's Ratio0.27
Tensile Strength (Ultimate)350 MPa50.8 ksi
Compressive Strength3,700 MPa537 ksi
Flexural Strength800 MPa116 ksi
Fracture Toughness (K_IC)5.5 MPa·√m5 ksi·√in
Hardness, Vickers1,800 HV
Hardness, Knoop1,650 HK
Hardness, Mohs9

Thermal5

Sialon AB is rated for continuous service to 1,300°C (2,372 °F). It conducts heat at 20 W/m·K (11.6 BTU/hr·ft·°F), worse than 55% of ceramic grades. Thermal expansion is 3 µm/m·K (1.67 µin/in·°F).

Thermal Conductivity20 W/m·K11.6 BTU/hr·ft·°F
Specific Heat Capacity690 J/kg·K0.16 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)3 µm/m·K1.7 µin/in·°F
Max Service Temperature (continuous)1,300°C2,372 °F
Min Service Temperature-200°C-328 °F

Electrical5

Sialon AB is an electrical insulator with a dielectric strength of 15 kV/mm (381 V/mil) and a resistivity of 1×10¹¹ Ω·m.

Electrical Resistivity1×10¹¹ Ω·m3.94×10¹⁸ µΩ·in
Dielectric Strength15 kV/mm381 V/mil
Dielectric Constant (1 MHz)7.9
Dissipation Factor (1 MHz)0.002
Volume Resistivity1×10¹³ Ω·cm

Chemical & Environmental2

Corrosion resistance is excellent (92/100), better than 88% of ceramic grades.

Corrosion ResistanceExcellent92/100
Chemical Resistance SummaryExcellent against most acids, molten aluminium and non-ferrous melts, slags and cryolite; attacked by HF, hot concentrated NaOH/KOH and molten alkali salts; slow passive oxidation in air above ~1200 °C.

Sustainability4

Producing a kilogram of Sialon AB takes about 230 MJ of energy and emits 14 kg of CO₂ — more than 65% of ceramic grades. Typical recycled content is 0%.

Embodied Energy (primary production)230 MJ/kg98,882 BTU/lb
Embodied Carbon (primary production)14 kg CO₂/kg
Embodied Water250 L/kg30 gal/lb
Typical Recycled Content0%

Manufacturability3

Sialon AB's machinability is not recommended (3/100, worse than 95% of ceramic grades).

MachinabilityNot recommended3/100
PolishabilityExcellent85/100
Sintering / Firing Temperature1,750°C3,182 °F

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

Working with Sialon AB

Is Sialon easy to machine?

Green/bisque machining is preferred; after sintering only diamond grinding, lapping or (TiN grade) EDM works — allow ~20 % shrinkage in green design.

Can Sialon be welded?

Not weldable; joined by active-metal brazing (Ti-containing AgCu filler), glass sealing or mechanical shrink/clamp mounts with compliant gaskets.

Can Sialon be formed, bent or molded?

Formed by uniaxial/cold-isostatic pressing, slip or injection moulding of Si3N4+AlN+Al2O3+Y2O3 powder, then pressureless or gas-pressure sintering at 1650–1850 °C in N₂; HIP for maximum density.

What surface finishes work on Sialon?

Diamond lapping/polishing to Ra < 0.05 µm; edges must be honed or chamfered to avoid chipping; CVD/PVD coatings (TiN, Al₂O₃) applied on cutting-tool grades.

Sialon 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
Sias β-Si6-zAlzOzN8-z, z ≈ 0.5–1.5 for engineering grades42 – 5850
N27 – 3634
Alsubstitutes for Si in the lattice3 – 149.5
Olattice O plus grain-boundary glass2 – 95.5
Y (as Y2O3 sintering aid)some grades use Yb2O3/Ce2O3 or MgO instead0.5 – 52.5
Si+Al+O+N balanceimpurities (Fe, Ca) typically < 0.5 %balance—

Sialon AB — frequently asked

What is Sialon AB used for?

Sialon AB is typically used for cutting inserts for nickel alloys, molten metal handling, thermocouple protection tubes and wear parts. In short: superalloy-turning insert ceramic; best thermal-shock nitride; EDM-capable TiN grade.

What is the tensile strength of Sialon AB?

Sialon AB has a typical tensile strength of 350 MPa (50.8 ksi) — stronger than 71% of ceramic grades. Strength varies by condition: see the 3 listed tempers.

Is Sialon AB easy to machine?

Not especially — machinability is rated not recommended (3/100, worse than 95% of ceramic grades). Green/bisque machining is preferred; after sintering only diamond grinding, lapping or (TiN grade) EDM works — allow ~20 % shrinkage in green design.

Can Sialon AB be welded?

Not weldable; joined by active-metal brazing (Ti-containing AgCu filler), glass sealing or mechanical shrink/clamp mounts with compliant gaskets.

What surface finishes work on Sialon AB?

Diamond lapping/polishing to Ra < 0.05 µm; edges must be honed or chamfered to avoid chipping; CVD/PVD coatings (TiN, Al₂O₃) applied on cutting-tool grades.

Can Sialon AB be formed, bent or molded?

Formed by uniaxial/cold-isostatic pressing, slip or injection moulding of Si3N4+AlN+Al2O3+Y2O3 powder, then pressureless or gas-pressure sintering at 1650–1850 °C in N₂; HIP for maximum density.

What is the maximum service temperature of Sialon AB?

Sialon AB is rated for continuous use to about 1,300°C (2,372 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Sources

  1. ISO 26845 — Chemical analysis of refractories, general requirements — ISO (2008)
  2. ASM Engineered Materials Handbook, Vol. 4: Ceramics and Glasses — ASM International (1991)
  3. Syalon 050 / 101 / 110 / 501 technical datasheets — International Syalon (2023)
  4. Silicon nitride & sialon cutting tool material data — Kyocera / CoorsTek (2022)

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.