A Guide on Laser Engraving and Marking Technology for Stainless Steel

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Stainless steel also called as Inox Steel or simply Inox in metallurgical terms, is an iron alloy that contains carbon and a minimum 10% chromium content. Presence of chromium leads to the development of a ‘passive layer’ on the surface of steel which prevents corrosion. More the content of chromium, more corrosion-resistant it becomes. Stainless steel may also contain silicon, manganese, nickel, titanium, copper, and molybdenum in varying proportions to impart its other characteristics such as enhanced formability, strength, cryogenic toughness, and corrosion resistance. Non-metal substances such as carbon and nitrogen may also be added to it for developing other properties.

Stainless steel is widely applicable in many industries owing to its durability, corrosion resistance, and moisture resistance. Also, it doesn’t contaminate other materials and doesn’t react with many chemicals. That is one reason why people use it heavily in hospitals and food processing industry. Some of its many applications include elevator panels, switch, containers, control panels, etc. The machinability of this metal, or how it responds to cutting processes vary from one grade to another. Let’s have a look at various ways of stainless engraving.

  • Diamond Drag Engrave: Also known as ‘scratch engraving,’ this is the most common and most straightforward type of engraving metals. It can be done either manually or with a computerized engraver. This method is usually applicable for removing the top coating to expose the metal underneath. The tool used in this method is a diamond graver which consists of a steel shank and a conical diamond fitted at one end. This type is appropriate for metal giftware items such as knife and cup.
  • Rotary Engrave: This type of engraving uses motorized spindle based rotating cutting tool. The tool cuts into the metal at a pre-specified depth to produce a gutter of the same dimension as the cutter. One can make this type of engraving on brass, aluminum, wood, hard steel, stainless steel, and plastic. It is usually appropriate for flat surfaces.
  • Chemical Etching Engrave: It is a subtractive machining process which uses etchant chemicals for producing complex patterns. This process creates depth on the surface which you can fill with paint, can bear harsh conditions and is extremely durable. It applies to many industries such as mining, commercial, aerospace, automotive, decorative, marine, and mechanical.
  • Laser Marking: There are three processes under this:
  • Direct Mark using a carbon dioxide laser and High-Power Density Focusing Optics. It creates a direct and permanent mark on the surface. This process can create highly intricate details. Although the slowest marking process, it doesn’t require clean-up. The spot sizes it produces are 0.001”.
  • Metal marking compound using carbon dioxide laser. This process requires applying marking compound on the surface and letting it dry. The compound gets heated by laser beam resulting in nearly permanent, high contrast black mark on the steel surface. It is used for general marking, barcodes, and images. The mark that this method produces is a raised surface, hence making it unsuitable for certain applications.
  • Direct mark using fiber laser. This process uses fiber laser, the heat of which causes oxidization to form a permanent mark. Depending on the settings, permanent dark, mid-tone or light marks with a variety of colors can be produced. It is a comparatively faster process and produces extremely fine details with spot sizes ranging from 0.00025” to 0.0025”.

What are the advantages of laser-engraving stainless steel?

Laser technology has paved the way for the production of high quality products in less time. Stainless steel allows direct marking on its surface for creating images that are not only resistant to temperature fluctuation and moisture, but it can also withstand corrosive and abrasive environments. There are multiple benefits of laser-engraving stainless steel. Logos, barcodes, customized labels, text or an image, can be created on stainless steel without any signs of deformation or stress caused due to the laser beam process. Very fine and intricate designs can also get easily created on the surface of this metal.

Some of its popular applications are in marking sports equipment, placement of the logo or serial numbers on machines and appliances, and laser etching equipment and other assets.

Laser systems for laser engraving:

  1. Flexible and integrable laser marking system: This system is suitable for companies that already have a laser system in place. Given its flexibility, it is ideal for any size of components.
  2. Laser system for safe and clean markings and engravings: This system is for processing small components of up to 10 kg. Its enclosed housing makes it suitable to use in all rooms without the need for advanced safety precautions. The materials that one can process are metal, plastic, wood, glass, ceramics, and organic materials.
  3. Laser system for marking and engraving heavy workpieces: This system is suitable for medium to heavy components weighing up to 115 kg.
  4. Laser System for marking, engraving, and lettering with linear actuator: This system features excellent laser beam quality and maximum precision. All kinds of steel materials and nonferrous metals, ceramics and glass can be labeled. With the aid of labeling software, graphics, logos, data matrix codes, and objects can be displayed. It is a no-contact and low-distortion process, processing workpieces weighing up to 1000 kg.
  5. All-in-one engraving and marking laser system: Appropriate for smaller components, this laser system has a built-in PC and software-based focal length. This system has broad applicability in the jewelry industry and processing of electronic components. One can use it on rubber strings, anodized aluminum, ceramics, plastic, and reflecting areas.

Laser engrave application in various industries:

  • Product labeling for protection against plagiarism
  • Product information marking such as batch number and date of manufacture
  • Codes for ease of traceability
  • Nameplates
  • Color laser marking in kitchen appliances
  • Color laser engraving for knife and cutlery manufacturers
  • The processor of steel parts and equipment.

The flexibility of this metal paves the way for its applicability across diverse industries.