B Scale vs. C Scale

Attribute	B Scale	C Scale
Origin	Developed by psychologist Raymond B. Cattell	Developed by psychologist John L. Holland
Number of factors	16 primary factors	6 primary factors
Focus	Personality traits	Vocational interests
Usage	Commonly used in personality assessment	Commonly used in career counseling

Introduction

When it comes to measuring hardness, the B Scale and C Scale are two commonly used methods. Both scales have their own unique attributes that make them suitable for different applications. In this article, we will compare the attributes of the B Scale and C Scale to help you understand the differences between them.

Accuracy

The B Scale is known for its accuracy in measuring the hardness of materials. It uses a 100 kg load applied for 15 seconds, which provides consistent and reliable results. On the other hand, the C Scale uses a 150 kg load applied for 30 seconds, which can sometimes lead to variations in measurements. This makes the B Scale a preferred choice for applications where precise hardness measurements are required.

Range

One of the key differences between the B Scale and C Scale is their respective hardness ranges. The B Scale covers a range of 100 to 700 on the Rockwell scale, making it suitable for measuring the hardness of softer materials. In contrast, the C Scale covers a range of 20 to 70 on the Rockwell scale, making it ideal for harder materials. This difference in range allows each scale to be used for specific types of materials.

Indenter

Another important attribute to consider when comparing the B Scale and C Scale is the type of indenter used. The B Scale uses a 1/16 inch diameter steel ball as the indenter, while the C Scale uses a 120-degree diamond cone. The choice of indenter can affect the accuracy and repeatability of hardness measurements, with the diamond cone providing a sharper and more precise impression compared to the steel ball.

Surface Finish

Surface finish is another factor that can impact the hardness measurements obtained using the B Scale and C Scale. The B Scale is more sensitive to surface finish variations, as the steel ball indenter can be influenced by surface imperfections. On the other hand, the C Scale is less affected by surface finish, thanks to the sharp diamond cone indenter. This makes the C Scale a better choice for materials with rough or uneven surfaces.

Applications

Both the B Scale and C Scale have their own unique applications based on their attributes. The B Scale is commonly used for softer materials such as plastics, lead, and aluminum, where precise measurements are crucial. On the other hand, the C Scale is preferred for harder materials like steel, hardened steel, and cemented carbides, where a higher load and sharper indenter are needed to penetrate the surface.

Conclusion

In conclusion, the B Scale and C Scale have distinct attributes that make them suitable for different hardness measurement applications. The B Scale offers greater accuracy and sensitivity to surface finish variations, making it ideal for softer materials. On the other hand, the C Scale provides a wider hardness range and is less affected by surface finish, making it better suited for harder materials. By understanding the unique attributes of each scale, you can choose the right method for your specific hardness measurement needs.