Ash · heat-treated state
Ash-TMT
Properties of the TMT condition, compared with the other Ash tempers.
Pick for cladding, decking and sauna parts where dimensional stability and decay resistance matter more than toughness.
What is Ash-TMT?
Ash-TMT is Ash heat treated to TMT — pick for cladding, decking and sauna parts where dimensional stability and decay resistance matter more than toughness. Ash-TMT has a tensile strength of 110 MPa (16 ksi), stronger than 97% of natural material grades. Elongation at break is 0.6% and the elastic modulus is 11.5 GPa (1.67 Msi). Ash-TMT has a density of 0.6 g/cm³ (0.0217 lb/in³), lighter than 66% of natural material grades. KD12 is the default condition FabDigit quotes; TMT is available on request or by drawing note.
Advantages
- Good corrosion resistance — 60/100, better than 76% of natural material grades
Limitations
- Low fracture toughness — 0.35 MPa·√m (0.319 ksi·√in), worse than 97% of natural material grades
- Limited ductility — 0.6%, worse than 84% of natural material grades
Ash-TMT properties
Typical room-temperature values for Ash-TMT — 12 properties are specific to this condition; the rest are grade-level values shared by every Ash temper. Each bar shows where the value sits among the natural material grades in FabDigit's library — further right is higher.
Physical2
Ash-TMT has a density of 0.6 g/cm³ (0.0217 lb/in³), lighter than 66% of natural material grades.
Mechanical9
Ash-TMT has a tensile strength of 110 MPa (16 ksi), stronger than 97% of natural material grades. Elongation at break is 0.6% and the elastic modulus is 11.5 GPa (1.67 Msi).
Thermal5
Ash-TMT is rated for continuous service to 110°C (230 °F). It conducts heat at 0.12 W/m·K (0.0693 BTU/hr·ft·°F), worse than 70% of natural material grades. Thermal expansion is 30 µm/m·K (16.7 µin/in·°F).
Electrical2
Ash-TMT is an electrical insulator with a dielectric strength of 3 kV/mm (76.2 V/mil) and a resistivity of 1×10⁸ Ω·m.
Chemical & Environmental1
Corrosion resistance is good (60/100), better than 76% of natural material grades.
Sustainability4
Producing a kilogram of Ash-TMT takes about 11 MJ of energy and emits 0.5 kg of CO₂ — more than 56% of natural material grades. Typical recycled content is 5%.
Manufacturability2
Ash-TMT's machinability is very good (75/100, worse than 60% of natural material grades).
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Other Ash tempers and conditions
Ash is also supplied in 3 other conditions. The full side-by-side table is on the Ash overview.
- KD12DefaultDefault commercial condition for indoor furniture, flooring, tool handles and sports goods.110 MPa tensile
- GRNPick for steam bending, turning blanks and riven handle stock that will be dried after shaping.75 MPa tensile
- ADChoose for sheltered outdoor joinery or shop stock that will be re-conditioned before final machining.8 properties
- TMTPick for cladding, decking and sauna parts where dimensional stability and decay resistance matter more than toughness.12 properties
Working with Ash-TMT
Is Ash easy to machine?
Saws, planes and turns cleanly with carbide tooling; moderate tool blunting and a tendency to tear-out at interlocked grain, so use sharp knives and light finishing cuts.
Can Ash be welded?
Not weldable — joined by PVAc/PU/epoxy adhesives (glues well) or mechanical fasteners; pre-drill near ends to avoid splitting.
Can Ash be formed, bent or molded?
One of the best steam-bending hardwoods: steam green or air-dried stock ~1 h per 25 mm and bend over a strap to tight radii.
What surface finishes work on Ash?
Coarse open pores need grain filler for a mirror finish; stains, oils and waterborne lacquers take evenly, and exterior use requires preservative or thermal modification plus UV-stable coating.
Ash 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.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| celluloseoven-dry basis | 40 – 47 | 44 |
| hemicellulosexylan-rich, typical of hardwoods | 22 – 30 | 26 |
| ligninsyringyl/guaiacyl type | 21 – 28 | 25 |
| extractivestannins, fats, sugars; higher in heartwood | 2 – 6 | 4 |
| mineral ashCa, K dominated | 0.2 – 1 | 0.6 |
| moisture (as supplied, KD)added on top of oven-dry substance | 8 – 14 | 12 |
Ash-TMT — frequently asked
What is Ash-TMT used for?
Ash-TMT is typically used for tool handles, baseball bats, hockey sticks, furniture and interior trim. In short: highest shock resistance here; excellent steam-bending hardwood; open-pore surface needs filler.
What is the tensile strength of Ash-TMT?
Ash-TMT has a typical tensile strength of 110 MPa (16 ksi) — stronger than 97% of natural material grades. Strength varies by condition: see the 4 listed tempers.
Is Ash-TMT easy to machine?
Yes — machinability is rated very good (75/100, worse than 60% of natural material grades). Saws, planes and turns cleanly with carbide tooling; moderate tool blunting and a tendency to tear-out at interlocked grain, so use sharp knives and light finishing cuts.
Can Ash-TMT be welded?
Not weldable — joined by PVAc/PU/epoxy adhesives (glues well) or mechanical fasteners; pre-drill near ends to avoid splitting.
What surface finishes work on Ash-TMT?
Coarse open pores need grain filler for a mirror finish; stains, oils and waterborne lacquers take evenly, and exterior use requires preservative or thermal modification plus UV-stable coating.
Can Ash-TMT be formed, bent or molded?
One of the best steam-bending hardwoods: steam green or air-dried stock ~1 h per 25 mm and bend over a strap to tight radii.
What is the maximum service temperature of Ash-TMT?
Ash-TMT is rated for continuous use to about 110°C (230 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
Sources
- Wood Handbook — Wood as an Engineering Material (FPL-GTR-190), mechanical properties of white/green ash — USDA Forest Products Laboratory (2021)
- EN 13556 — Round and sawn timber: nomenclature of timbers used in Europe (FRAX) — CEN (2003)
- EN 350 — Durability of wood and wood-based products, natural durability classes — CEN (2016)
- The Wood Database — Fraxinus excelsior / Fraxinus americana species data — wood-database (2023)
- Thermally modified ash cladding technical data (Thermory/ThermoWood class D) — International ThermoWood Association (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.