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inside surface 3D photochem_edited
De-can clean removal
decorative milling
Surface milling
selective milling
surface enhancement
surface conditioning
taper milling
Photoresist 3
Surface Milling
Post Processing

Additive Metal Chemical Post-processing

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Whatever your industry, Tech Met has a solution for your metal post processing needs

Post process finishing can make or break the best designs.  Tech Met solutions are designed for aggressive removals within tight tolerances to allow for a uniform surface that permits interpretability while minimizing the risks of hydrogen pick-up and grain boundary attack.  

A key partner in the supply chain of traditionally manufactured aerospace and medical components, Tech Met is uniquely positioned to provide post processing services for additively manufactured metal hardware.
Tech Met began working with 3D printed alloys more than a decade ago to provide advanced methodologies for high quality post processing.  Today, Tech Met is providing chemical milling and surface treatment services for some of the world’s most advanced additive applications including NASA rocket engines.  


Tech Met solutions have been used successfully on medical implants both additive and traditionally machined. Tech Met’s patented and proprietary surfaces promote osteogenesis.

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Chemically milled surfaces on titanium implants

Chemical Post processing can improve the quality of parts and ensure that they meet their design specifications. These finishing processes can enhance a part’s surface characteristics, geometric accuracy, aesthetics, mechanical properties, and more.  Some typical applications for Tech Met’s chemical printed alloy surface treatment operations are:

  • Long term fatigue improvement

  • Removal of surface scale

  • Surface roughness reduction

  • Surface preparation for penetrant inspection

  • Removal of internal and external support structures

  • Removal of surface particles and powder entrapment

Download our whitepaper on the advantages of chemical post-process on additive manufactured parts below.

Chemical post processing of internal and external support structures on printed Inconel 718

Chemical post processing of internal and external support structures on printed Inconel 718

Available today on a wide variety of alloys  and high temperature corrosion resistant alloys including:

  • Titanium alloys

  • Aluminum alloys 

  • Inconels 718 /625

  • Steel alloys

  • Niobium C103

  • Cobalt Chrome Moly

  • Haynes Alloys

  • Hastelloys


As the additive manufacturing industry continues to evolve and mature, Tech Met will continue to take the lead in providing cutting edge solutions.

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Post Processing - A closer look

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Post processing of Cobalt Chrome shows dramatic reduction in surface particles and surface Ra improvement.  The nodules of powder in the left hand view are essentially gone at .008" removal.  Bonded metal structure underneath is now visible in right side view. 

Particle Removal Printed Cobalt Chrome

Tech Met can provide an effective, economical solution for your post processing requirements and is available for a wide variety of high temperature alloys.

Printed A205 Aluminum Alloy  (lPre-etch left view, Post-etch on right )

post processing 3D printed alloys, printed part finishing, surface treatment printed parts
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Whatever your metal post processing needs, let Tech Met work with your team to provide a unique solution to hardware realization and stabilization.

Surface topography pre and post milled on printed Titanium 6:4, 0.001” removal

Custom and Standard Chemical Milling

Chemical Milling

Tech Met can chemically mill features, size parts, remove weight and prepare surfaces by removing unwanted surface material.  

  • Selective & Global Milling

  • Decorative & Taper Milling

  • 3D Photoetching

Surface Milling

Chemical milling is the process of removing surface material using chemical dissolution.  Tech Met can chemically mill features, size parts, remove weight and prepare surfaces by removing unwanted surface conditions.  


The removal process can be a global removal on all surfaces of a component or performed selectively, using masking techniques to provide pockets of removal or patterns as required by the application.


Precise removals are accomplished by continuous monitoring and active process control to include careful control chemistry, engineered part agitation, and extensive process knowledge.


By continuous monitoring, extensive process knowledge and active process control of chemical, thermal, mechanical and temporal parameters.

hi-temp alloy, surface milling, surface texturing medical implants

Selective Chemical Milling

chemical milling, thin wall tubing, hi-temp alloy
hi-temperature alloy milling

To achieve selective milling Tech Met provides masking using bath dip and airless spray applications including robotic spray application techniques in specific cases for consistency and control.


Scribing is done using customer supplied templates or templates developed in house.  In some cases laser scribing is used to precisely locate the desired pockets.


Removal depths and locations of selective pockets are engineered and quality certified to meet all drawing specifications.

Parts are precisely masked to ensure that only the specified areas of the piece is chemically milled

Taper Milling

Chemical milling to produce progressively tapered thicknesses in sheet, bar and tube components made from any of the alloys that can be milled. Taper milling can be used to repair collapsed casings, liners or tubing, designed to clean without cutting or damaging the surfaces.  Chemical taper mills are available in various sizes and configurations. 

Tapered milling is performed by lowering and raising the work piece in and out of the milling solution as it etches.  The rates of movement are matched to the part requirements and controlled through automated systems. Though typically performed to create linear tapering, varying the speeds of immersion and extraction with the curvature of the workpiece allows curved features to be tapered as well. 

thin wall tubing, chem milling

Tapered or Contoured milling can facilitate customer removal profiles across lengths up to 24 feet

Decorative Pattern Milling

decorative patter milling, architectural chemical milling

Tech Met can use various techniques to produce etched patterns or printed art effects on large flat panels for architectural applications. Techniques include pattern screening or laser scribing of maskants to produce the desired pattern.

Using chemical milling to create surface geometry and textures for architectural applications

3D Chemical Etching, Photo chemical etching
3D Photo Chemical etching

3D Photo Chemical Etching

Flat as well as 3D curved surfaces can be precisely etched to tight tolerances of up to 0.00025". Through chemical milling, we accurately etch patterns on a wide range of materials.  Photo chemical etching produces highly complex parts with very fine detail and dimensional repeatably.  

Part detail pre and post photo chemical etching on a 3D curved surface

Surface Enhancements

  • Improve bond strength

  • Proprietary surface texturing for medical implants

  • Surface conditioning and Purification

  • Titanium Recast removal

surface enhancements
surface purification, hi-temp alloy chemical milling

Chemical milling can be used to remove unwanted surface conditions such as EDM recast layers, oxidation layers, heat affected layers, Alpha case and metal contamination.

Parts are submerged into carefully monitored chemical baths for precise periods of time to achieve specified depth removal.  Etch rate varies on a number of factors, including the concentration and composition of the etchant, the material, and temperature conditions. 

Surface Conditioning and Purification

Chemical milling used to remove recast layer from the surface of an EDM metal part.

Download our Titanium Recast removal service bulletin here

Surface Texturing

Tech Met has developed (and patented) unique surface texturing processes that can be applied on most materials (including titanium and cobalt chrome) implant devices.  When utilized on implant devices the unique features of these surfaces provide exceptional osseointegration as well as many other advantages over textures.   The distinctive surface textures developed by Tech Met to promote bone on-growth have been adapted to a variety of medical implants as well as other applications requiring enhanced surface for the bonding of metal to composites. 

Surface texturing dramatically improves adhesion and bond strength, surface texturing medical implants, hip implants texturing, surface texturing spinal implants

Surface texturing in medical applications promote rapid and secure bone fixation.

chemical milling thn wall tubing, high temperature alloy chemical milling

Chemical  texturing  increases surface area to dramatically improve adhesion and strength in metal to composite bonding.

Other Services


Tech Met offers a variety of other services including:

  • R & D Engineering Consulting

  • HIP Can Removal

  • Passivation

Other Services

HIP Can Removal

Tech Met has extensive experience in the removal of steel and stainless steel “cans”  from Hot Isostatic Pressed (HIP) and extrusion consolidated components. This is an effective means of can removal for production parts or billets, or even for the recovery of HIP and extrusion consolidated scrap. Removal is done without affecting the underlying alloy component. 

Similar methods may also be used for the removal of tramp metal contamination or surface oxide contamination.  Typical applications include removal of oxides from titanium, steel can removal or removal of steel tooling embedded in Inconel alloy billet end cutoffs.  Complete removal of these contaminants allows the recovery of these high value materials without degradation of their composition.

high temperature alloy chemical milling
titanium alpha case removal, high temperature alloy chemical milling

Stainless steel component shown before and after HIP can removal


passivation stainless steel, alpha case removal

Passivated metal surface on a 300 series stainless steel part

The passivation process returns the stainless steel or other metals back to its original specifications by removing unwanted debris and oils from the surface.  Tech Met is proficient  in the production of passivated surfaces that comply with a variety of industrial specifications including QQ-P-35, ASTM 967, ASTM A380 and other processes. 

Advantages of Passivation

  • Cleanliness

  • Corrosion Resistance

  • Uniform Appearance

  • Deburring

  • Longevity

R&D Services

chemical milling, high temperature alloy, thin wall tubing

Many of our customers with great ideas have been turned away by other vendors telling them that "it" can't be done.  Tech Met takes pride in figuring out the impossible.  Tech Met's team of engineers and seasoned technical experts will find a solution to meet your toughest requirements.  With a line dedicated to R&D, prototyping and short runs and staffed with project managers that will go the extra mile.  Tech Met routinely tackles the highly complicated.

Call Tech Met today for a project consult.

Solving the toughest problems and providing quick turn solutions on a dedicated R&D line.

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