Which method of direct marking is the best?

• A. Hand engraving
• B. Stamping
• C. Ink jet
• D. Laser etching

Answer: (C)

Direct marking needs to be non-contact, fast, and capable of producing legible, durable codes on a variety of surfaces and shapes for traceability. Ink jet stands out because it deposits ink directly onto the surface without removing material, so there’s no heat-affected zone or deformation. Modern Industrial inkjet systems use robust inks—often UV-curable or ceramic-based—that resist heat, solvents, and abrasion, giving clear serial numbers or data matrix codes that survive service conditions. It can mark quickly on curved or irregular surfaces and supports high-volume production with flexible font sizes and code formats, making it cost-effective and adaptable.

Hand engraving is accurate but slow and can introduce surface roughness; stamping requires hard tooling and is less adaptable to complex shapes; laser etching is very durable but can be more expensive and slower for high-volume marking and can affect coatings on some parts. Ink jet offers the best combination of speed, versatility, and durability for direct part marking in many production environments.