The cold forming process in which a hardened tool is pressed against a workpiece (when there is relative motion between the tool and the workpiece) to produce a roughened surface with a regular pattern is

The correct option is Knurling.

Step-by-Step Explanation:

1. Understanding the Process Description:
The question describes a cold forming manufacturing process where a hardened tool (a knurling tool containing a specific pattern) is pressed against a rotating workpiece. The relative motion between the tool and the workpiece causes the pattern on the tool to be plastically deformed and impressed onto the surface of the workpiece, creating a roughened surface with a regular, textured pattern (typically straight or diamond-shaped).

2. Analyzing the Options:
• Knurling: This is a manufacturing process, typically conducted on a lathe, whereby a visually textured, regular pattern is rolled into the surface of a workpiece using hardened rollers. It is primarily used to provide a better gripping surface on handles, knobs, or thumb-screws. This matches the definition in the question exactly.
• Strip rolling: This is a metal rolling process where flat sheets or strips of metal are reduced in thickness by passing them through rollers. It does not produce a regular roughened gripping pattern.
• Roll forming: This is a continuous bending operation where a long strip of metal (typically coiled steel) is passed through consecutive sets of rolls or stands to bend it progressively into a desired cross-sectional profile.
• Chamfering: This is a machining process that cuts away an edge to create a beveled slope or transitional edge between two faces, rather than forming a textured pattern over a surface area.

3. Conclusion:
Therefore, the process described is indeed knurling.