While measuring surface texture, the part of the profilometer that makes contact with the workpiece surface is:

Explanation:

Surface Texture Measurement

Definition: Surface texture measurement is a critical aspect in manufacturing and engineering that involves evaluating the surface characteristics of a material or part. The surface texture includes various attributes such as roughness, waviness, and lay, which can significantly affect the performance, aesthetics, and longevity of the part.

Working Principle: To measure surface texture, an instrument known as a profilometer is used. The profilometer traverses across the surface of the workpiece to record the topographical features. The part of the profilometer that makes contact with the workpiece surface is crucial for capturing accurate measurements.

Correct Option Analysis:

The correct option is:

Option 2: a finely pointed stylus

This option correctly identifies the part of the profilometer that makes contact with the workpiece surface. The finely pointed stylus is responsible for tracing the surface profile, detecting and recording the minute variations in texture. This contact method allows for precise measurement of surface roughness and other texture parameters.

Advantages:

• High precision in measuring surface irregularities, providing detailed and accurate surface texture data.
• Capability to measure very small surface features, which is essential for high-precision engineering applications.

Disadvantages:

• The contact nature of the measurement can sometimes cause wear on both the stylus and the workpiece surface.
• Not suitable for very soft or delicate surfaces where the stylus might cause damage.

Applications: Surface texture measurement with a finely pointed stylus is widely used in various industries, including automotive, aerospace, and precision engineering, where high surface quality is critical.

Additional Information

To further understand the analysis, let’s evaluate the other options:

Option 1: an electrical pickup

An electrical pickup typically refers to a component used in various electronic instruments to convert physical quantities into electrical signals. While profilometers may use electrical pickups to process the signals generated by the stylus, the electrical pickup itself does not make direct contact with the workpiece surface.

Option 3: a motorised mechanism

A motorised mechanism in a profilometer is responsible for moving the stylus or the workpiece to ensure a consistent and controlled measurement process. However, the motorised mechanism does not make contact with the workpiece surface; it simply facilitates the movement of the stylus.

Option 4: a recording unit

The recording unit in a profilometer is used to capture, process, and display the surface texture data obtained from the stylus. While it is an essential part of the measurement system, it does not make direct contact with the workpiece surface.

Conclusion:

Understanding the components and their functions in a profilometer is crucial for accurate surface texture measurement. The finely pointed stylus is the part that directly interacts with the workpiece surface, making it integral to capturing detailed surface characteristics. This contact method allows for high precision in measurements, though it requires careful handling to avoid damage to both the stylus and the workpiece.