What are the mechanical properties of wood?
The mechanical properties of wood include strength in tension and compression (as measured in axial and transverse directions), shear, cleavage, hardness, static bending, and shock (impact bending and toughness).
What is the bending property of wood?
In the direction of the grain, the bending strength is directly proportional to the density of the wood. In uniform, flawless wood, the bending strength is as great as the tensile strength. Tensile strength in the direction of the grain is usually 10-20 times more than its strength perpendicular to the grain.
What are mechanical properties?
Mechanical properties are physical properties that a material exhibits upon the application of forces. Examples of mechanical properties are the modulus of elasticity, tensile strength, elongation, hardness and fatigue limit.
What is mechanical properties of solids?
Mechanical Properties of solids describe characteristics such as their strength and resistance to deformation. Examples of mechanical properties are elasticity, plasticity, strength, abrasion, hardness, ductility, brittleness, malleability and toughness.
What are chemical properties of wood?
Wood has the chemical property of flammability. Flammability is the ability of a substance to burn. Ash and smoke cannot burn, so they have the chemical property of non-flammability.
What are materials properties?
The material properties are size, shape, density of the particles, and their intrinsic mechanical properties (Young’s modulus, yield stress, fracture toughness, etc.
What is the strength properties of wood?
Relationship between Mechanical Properties and Anatomical Structure of Wood
| Property | n | A90/A0 |
|---|---|---|
| Tensile strength | 1.5–2 | 0.04–0.07 |
| Compression strength | 2–2.5 | 0.03–0.40 |
| Bending strength | 1.5–2 | 0.04–0.10 |
| Modulus of elasticity | 2 | 0.04–0.12 |
How do you find the compressive strength of wood?
Engineers measure the compressive strength by loading a block of wood parallel to the grain until it breaks, and the bending strength by loading a block perpendicular to the grain. Both are measured in pounds per square inch (psi).
How is Technora prepared and what are its properties?
Technora® exhibits high mechanical properties and resistance to chemicals. It is prepared from p -phenylenediamine, 3,4′-diaminodiphenylether, and terephthaloyl dichloride in an amide solvent with a small amount of alkali salt at 0–80 °C (eqn [10] ). 44 where m = 0.25, n = 0.25, and k = 0.5.
What are the tensile properties of Technora yarn?
The typical tensile properties of Technora multifilament yarns are 28 g den−1 tenacity, 590 g den −1 tensile modulus, and 4.6% elongation at break. Fig. 16 compares the stress–strain behavior of Technora fiber and other industrial fibers.
What is the specific heat of Technora fiber?
The specific heat of Technora is 0.26 cal g −1 °C −1 compared with 0.4 cal g −1 °C −1 for PPD-T fiber. Technora Fiber exhibits creep of the order of 0.25–1.5% at 20–150°C under tensions of 1–5 g den−1 for 24 h. Technora fiber is dimensionally stable at temperatures up to 200°C.
What is the specific heat of combustion of Technora?
Technora fiber decomposes at 500°C compared to 550°C for PPD-T fiber. The ignition point of Technora is about 650°C. Its heat of combustion is 6800 cal g−1. The specific heat of Technora is 0.26 cal g −1 °C −1 compared with 0.4 cal g −1 °C −1 for PPD-T fiber.