What is Tensile Strength?
Tensile strength, one of the fundamental properties of materials, is measured by using a tensile test. This test involves taking a standard sample of a material, often in the shape of a bar or a rod, and subjecting it to an axial load or force until it fractures. The maximum stress the material can withstand before it breaks, which is usually expressed in units of force per cross-sectional area (like pascals or pounds per square inch), is its tensile strength. A machine known as a tensile tester or a universal testing machine is typically used to perform this test. The machine progressively increases the force applied to the material while simultaneously recording the change in the material's length. By plotting these values on a graph, known as a stress-strain curve, scientists and engineers can evaluate the tensile strength and other related properties of the material.
The History of the Tensile Test;
The history of the tensile strength test stretches back to the early days of industrialization in the late 18th and 19th centuries. During this time, the need to understand the properties of materials grew as increasingly complex structures, like bridges and buildings, were being built. People began to realize the importance of understanding the strength and durability of the materials they were using.
One of the earliest instances of tensile testing was conducted by Thomas Tredgold, an English engineer, in 1822. He performed rudimentary tensile tests on cast iron and timber to understand their strength. These early tests were far from the standard procedures used today, but they laid the foundation for the future of material testing.
The real breakthrough came with the development of the Universal Testing Machine (UTM) in the late 19th century. The UTM, originally created by Albert Ubbelohde in the United Kingdom, allowed for more precise and consistent testing. These machines were capable of applying a controlled force on a material and measuring the deformation, enabling engineers to calculate the tensile strength with more accuracy.
Throughout the 20th century, tensile testing procedures became standardized, leading to more reliable and comparable results. With the advent of computers and automation in the latter part of the century, the process of tensile testing became even more precise and efficient. Tensile testing has now become a fundamental part of material science and engineering, crucial in industries ranging from construction to aerospace to textiles, helping manufacturers and engineers understand the properties of materials and make informed choices.
Why the tensile test is relevant when clothes shopping;
The tensile strength of a material, revealed through a tensile test, is a key indicator of the durability and longevity of the garment. This is particularly relevant for shoppers considering hemp clothing. Hemp has a high tensile strength, meaning it can endure significant stress without breaking or losing shape. This characteristic makes hemp clothing resilient to wear and tear, promising a longer lifespan for the garment compared to others made from different materials. Therefore, understanding tensile strength can help shoppers make more informed choices, ensuring that they invest in clothing that not only aligns with their style preferences but also provides excellent durability and value for money. This becomes even more pertinent given the growing interest in sustainable fashion, where the durability of clothing plays a significant role in reducing waste and promoting responsible consumption.
How does hemp compare?
When it comes to durability, hemp truly shines, especially when compared with other popular textiles like cotton. In tensile tests, which measure a fabric's resistance to breaking under tension, hemp consistently outperforms cotton. Hemp fibers are known to have one of the highest tensile strengths among natural fibers, which results in hemp clothing withstanding regular wear and frequent washings far better than cotton. This means hemp garments retain their shape and integrity for longer, contributing to their overall longevity.
As for wool, while it does exhibit a commendable level of durability, it can't quite compete with hemp. Wool garments can shrink and deform over time, especially when exposed to heat and moisture, making them less enduring than their hemp counterparts.
When it comes to synthetic fibers, like polyester and nylon, they often match hemp in tensile strength. However, their durability comes at the expense of comfort and environmental sustainability. Synthetic fibers don't breathe as well as hemp, leading to less comfortable clothing, particularly in warmer weather. Moreover, they lack the UV resistance and antibacterial properties inherent in hemp, which contributes to the durability of hemp clothing over the long term. Additionally, synthetic fibres involve non-renewable resources in their production and are less biodegradable, posing significant environmental & health concerns.
Taking a holistic perspective on durability—factoring in tensile strength, wearability, and environmental impact—hemp is clearly the superior choice. One barrier to making the switch to hemp clothing used to be price, however a greater interest in sustainable fashion is driving up the demand and therefore supply of hemp fibre bringing down its cost. In fact, at Hempstitch, we are so committed to making it easy for our customers to make the switch that we’ve launched the Venture By Hempstitch range of affordable hemp basics to suit shoppers at every price point.