Sagot :
Answer:
Early Hardness Testing
Hardness, as applied to most materials, and in particular metals, is a valuable, revealing, and commonly employed mechanical test that has been in use in various forms for over 250 years. Certainly, as a material property, its value and importance cannot be understated, the information from a hardness test can complement and often be used in conjunction with other material verification techniques such as tensile or compression to provide critical performance information. How important and useful is material and hardness testing? Consider the information provided and its significance in structural, aerospace, automotive, quality control, failure analysis and many other forms of manufacturing and industry. Determining these material properties provides valuable insight to the durability, strength, flexibility, and capabilities of a variety of component types from raw materials to prepared specimens, and finished goods. Over the years, various methods for determining the hardness of materials have been developed and employed at varying levels of success. From early forms of scratch testing to sophisticated automated imaging, hardness testing has evolved into an efficient, accurate, and valued material test method.
Buehler Materials
History of Hardness
Buehler Literature - History of Hardness
Early Hardness Testing
Hardness, as applied to most materials, and in particular metals, is a valuable, revealing, and commonly employed mechanical test that has been in use in various forms for over 250 years. Certainly, as a material property, its value and importance cannot be understated, the information from a hardness test can complement and often be used in conjunction with other material verification techniques such as tensile or compression to provide critical performance information. How important and useful is material and hardness testing? Consider the information provided and its significance in structural, aerospace, automotive, quality control, failure analysis and many other forms of manufacturing and industry. Determining these material properties provides valuable insight to the durability, strength, flexibility, and capabilities of a variety of component types from raw materials to prepared specimens, and finished goods. Over the years, various methods for determining the hardness of materials have been developed and employed at varying levels of success. From early forms of scratch testing to sophisticated automated imaging, hardness testing has evolved into an efficient, accurate, and valued material test method.
While testing techniques and hardware has significantly improved, particularly in recent years and in step with rapidly advancing electronics, computer, hardware, and programming capabilities, earlier, basic forms of hardness testing, such as the simple scratch test, sufficed for the need of the relevant era. Some of the earliest forms of bar scratch testing date back to about 1722. These tests were based on a bar that increased in hardness from end to end. The level at which the material being tested could form a scratch on the bar was a determining factor in the specimens hardness. Later, in 1822, hardness testing forms were introduced that included scratching material surfaces with a diamond and measuring the width of the resultant line, a test eventually known as the Mohs scale. In some processes this method is still utilized today.
Explanation:
I don't know if you can understand that but okay if you don't understand my answer that's my opinion ^_^