Properties of Wood

Dhristi JEE 2022-24

Wood Plant Tissue and Properties of Wood

Wood is the second most used material for construction purposes, making of furniture, flooring, etc. For building constructions, though the stone has taken first place, the boom of wood has increased dramatically in recent times. Let's see more interesting facts about wood, different physical, chemical, mechanical, properties of wood.


Tissue Composition of Wood

Wood is a natural resource that can be obtained by plants and trees. Basically wood is a combination of different tissues like the xylem, which is a vascular tissue, phloem, and cell walls. The vascular cambium layer which is present inside the bark helps to produce new wood.


Properties of Wood

The properties of wood explain its behaviour, and how it reacts to different substances at different temperatures. These properties explain the characteristics of wood with a generalized meaning. The properties of wood may include physical properties, chemical properties, mechanical properties. The physical properties of wood can be defined as the characteristics of a wood that do not have any change in its size, shape, colour, etc.


Physical Properties of Wood

The characteristics of wood that explain the physical features of various types of wood are nothing but the physical properties of wood. They are explained as follows.


Colour - As the basic use of wood is to make furniture and decor items for the house, colour and appearance play a vital role in choosing a variety of wood. But the colour of the wood varies from type to type. The wood is available in a wide range of colours starting from white to dark brown etc. The colour of the wood also changes with the observation. If a tree can be observed from top to bottom, it appears in some colour and vice versa.


Lustre - Another physical property of wood is its lustre. Luster refers to the tendency of elements with the reflection of light. After colour, priority is given to the lustre of the wood.


Odour and Taste - We commonly observe different odours from different types of wood. For example, the sandalwood and the rosewood give a nice aroma whereas the other timber woods may give some tobacco odour. Also, the new wood sample gives a fresh aroma and it keeps on degrading with time.


The density of Wood - Another characteristic of wood is its density. But what is the density of wood? The density of wood refers to its mass per unit volume. Based on the weight of the wood sample, the density of wood changes. Different types of wood have different densities. Below detailed information about the density of different types of wood is given.

  • If the density or specific gravity is 36 then the wood is called very light.

  • When density or specific gravity is = 0.36 then the wood is called light.

  • If the density or specific gravity is 0.36 – 0.05, then wood is considered moderately heavy.

  • When density or specific gravity is > 0.05, then the wood is heavy.


Hardness - Hardness refers to the strength of the wood also the resistance or the capacity of wood which can stand strong for a long time after being affected by several factors. 


Mechanical Properties of Wood

The mechanical properties of wood can be explained as the capability of wood to withstand externally applied forces. These include different types of properties to understand the strength, resistivity, elasticity, durability, etc. many more characteristics of wood. The mechanical properties of wood were further classified into two. One is strength properties and the other is elasticity properties. There are different standards available to check the strength of wood. They are - 

  • ISO (International standard institution

  • ISI (Indian standard Institution)

  • BSI (British Standard Institution)

  • PSI (Pakistan Standard Institution)


Compression - The compression of wood depends on the directions of applied forces, like - 

  • perpendicular to wood grain

  • parallel to wood grain, and 

  • an angle to the wood grain.


Tension -  The tension is very effective on wood when it is parallel to the wood's grain.


Bending - Based on the load put on the wood, bending may occur. It shows the strength and stability of wood even if the load is increased in a parallel direction.


Conclusion

Wood is one of the most important materials used for several household and commercial purposes. Different types of physical properties and mechanical properties of wood explain the characteristics of a particular type of wood. All these properties were generalized to all types of wood. Few differences may occur accordingly.

FAQs on Properties of Wood

1. What are the Thermal and Electrical Properties of Wood?

The thermal and electrical properties of wood explain the conductivity of wood. If we take electric conductivity, it is the capability of wood to conduct and let electricity pass through it. Based on its ability, it is determined whether it is a good conductor of electricity or a bad conductor of electricity. Similarly for thermal conductivity.

  • Wood is not a good conductor of both heat and electricity.

  • But it can conduct both heat and electricity in a less amount when compared to iron, bricks, etc.

  • The direction and the density of the wood sample also determine the rate of flow of heat through it.

  • Size, structure, dryness of wood also affects the conductivity of wood.

2. Name Some Factors that Affect the Strength of the Wood.

The basic characteristics of wood are its strength and resistivity. But the strength of wood can be affected by various factors. These factors are known as risk factors of wood. They are as follows- 

  • The density of wood is for various types of wood samples. This in turn affects the strength of the wood.

  • If the moisture content percentage is more, the thermal conductivity of wood gets decreased. It reduces the strength of the wood.

  • Time of loading also acts as a risk factor for the strength of wood.

  • The strength of wood also gets affected by the temperature. The unsupportive climatic conditions and abnormal temperatures will affect the strength of the wood.

3. What are wood's thermal and electrical characteristics?

Wood conductivity is explained by its thermal and electrical properties. Electric conductivity refers to the ability of wood to conduct electricity and allow it to pass through it. It is decided if it is a good conductor of electricity or a bad conductor of electricity based on its capabilities. The same can be said for heat conductivity.


Heat and electricity do not conduct well through the wood. When compared to iron, bricks, and other materials, it can conduct heat and electricity in less proportion.


The rate of heat flow through the wood sample is also determined by the direction and density of the wood sample. The conductivity of wood is also affected by its size, structure, and dryness.

4. Identify some factors that affect the wood's strength.

Wood's strength and resistance are its primary attributes. However, a variety of factors can influence the strength of wood.


These are referred to as wood risk factors. The list is as follows: -

  • The density of wood varies depending on the type of wood sample. This, in turn, has an impact on the wood's strength. The heat conductivity of wood is reduced when the moisture content percentage rises.

  • It decreases the wood's tensile strength. The time of loading is also a risk factor for wood strength.

  • The temperature has an impact on the strength of wood. The wood's strength will be affected by unfavourable weather conditions and unusual temperatures.

5. What are the Wooden Characteristics?

The properties of wood explain how it behaves and reacts to various substances at various temperatures. These features provide a broad explanation of wood's characteristics.

  • Physical, chemical, and mechanical properties are some of the characteristics of wood.

  • The physical attributes of wood are the features of a wood that do not alter in size, shape, colour, or other aspects.

Wood's Physical Properties

The physical properties of wood are the qualities of wood that describe the physical aspects of distinct types of wood. The following are the explanations.


Colour: Because the most common use of wood is to construct furniture and decorative items for the home, colour and look are important considerations when selecting a type of wood. However, the colour of the wood varies according to the species. The wood comes in a variety of colours, ranging from white to dark brown and beyond. With each inspection, the colour of the wood changes. If you look at a tree from top to bottom, you'll notice that it has a different colour on each side, and vice versa.


Lustre: The shine of wood is another physical characteristic. The tendency of elements to reflect light is referred to as lustre. The shine of the wood takes precedence over the colour.


Odour and taste: Different scents and tastes are regularly observed from various types of wood. The sandalwood and rosewood, for example, have a pleasant perfume, whereas the other forest woods may have a tobacco odour. Furthermore, the new wood sample has a fresh aroma and continues to degrade over time.

6. What are Wood's mechanical properties?

Wood's Mechanical Properties The ability of wood to endure externally applied forces can be defined as its mechanical characteristics.


These include a variety of attributes that help you understand the strength, resistivity, flexibility, and durability of wood, among other things.


Wood's mechanical properties were divided into two categories. There are two types of properties: strength and flexibility.


There are a variety of standards for determining the strength of wood.


ISO (International Organization for Standardization) is one of them.


IST (Indian Standard Institution) BSI (British Standard Institution) PSI (Polish Standard Institution) (Pakistan Standard Institution) are the other two.


Wood compression is affected by the direction of applied forces, which might be perpendicular to the wood grain, parallel to the wood grain, or at an angle to the wood grain.


Tension - When applied parallel to the grain of the wood, tension is particularly effective.


Bending may occur depending on the load placed on the wood.

7. What is the Density of wood?

Wood's Density - Another feature of wood is its density. What is the density of wood, though?


The mass per unit volume of wood is measured by its density. The density of wood varies depending on the weight of the wood sample.


The density of various species of wood varies.


Below is thorough information on the density of several types of wood.


When the density or specific gravity of a piece of wood is 36, it is referred to as "extremely light."


When the density or specific gravity of the wood is less than 0.36, it is referred to as light wood.


Wood is termed moderately heavy if its density or specific gravity is between 0.36 and 0.05.


When the density or specific gravity of the wood exceeds 0.05, it is considered heavy.

Comment