DPM is the process of marking a permanent 2D machine-readable symbol, such as data matrix, directly onto a part's surface in order to support its integration into the production process.  It improves the speed and accuracy of data transfer, improves traceability, performs serial number duplication checks, and reduces the risk of look-ha-like parts being used for the wrong application.  The four primary methods of DPM are laser, ink jet, dot peen, and electro-chemical etch (ECE).

Application Methods:

Laser Marking. This is the practice of using lasers to engrave or mark an object.  The movements of the laser head are computer driven. By using two different types of laser machines (IAG and CO2) it is easy to mark a wide variety of surfaces and objects including natural materials, plastic, metals, coated metals, stone, glass, jewelery and fine arts.  Advantages of this method are speed, extreme precision and high code density.  However, the method provides low contrast on some materials.  It is widely used on semiconductors, medical and some automotive applications.

Dot Peen Marking. This is the practice of marking a component or part by striking a carbide or diamond tipped marker stylus against the surface of the material being marked.  The advantages of this technique are that the process contains no consumables, the marking is permanent, not affected by heat, and can sometimes be coated over and still be legible.  Its disadvantages are that the process is noisy, the marks don't provide much contrast for reading, and parts must be secure while marking.  Dot Peen Marking is widely used in automotive and aerospace applications.

Electro-Chemical Marking. This process is used to mark or engrave a metal object such as industrial, automotive, aerospace or medical components.  This process is also referred to as Electro-Chemical Etching (ECE).  It removes material from metallic surface by electrolysis. The marking will typically be used to identify a component or part using the Data Matrix standard.  Electro-Chemical marking does not cause stress fractures, is permanent and does not raise the surface being marked.  Also, it can be used to mark off-shaped parts.  This process can be used to mark any object that has a conductive metal surface.