Electrolytes for Sustainable Laser-Chemical Machining of Titanium, Stellite 21 and Tool Steel X110CrMoV8-2

Hauser, Olga; Mehrafsun, Salar; Vollertsen, Frank

doi:10.4028/www.scientific.net/amm.794.262

Cited by 3 publications

(5 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…With respect to the electrolyte solution the self-passivation of the used material is usually required in laser chemical machining. The LCM of Stellite 21 in phosphoric acid environment shows, as expected, similar behavior compared with other self-passivating materials, such as titanium [23], memory shape alloys (e.g. nickel-titanium alloys) [12] and stainless steel [24].…”

Section: Influence Of Self-passivation Property On the Machining Qualitysupporting

confidence: 75%

Removal behavior and output quality for laser chemical machining of tool steels

et al. 2019

View full text Add to dashboard Cite

Laser chemical machining represents a promising technology for manufacturing metallic micro parts. It is usually based on the selective thermal activation of electrochemical material dissolution of self-passivating metals in an electrolyte environment. Prior to widespread industrial acceptance, its machining quality needs to be classified within the subtractive machining processes and the range of machinable materials needs to be expanded. For this purpose, line and square cavities with dimensions ≤300 μm are machined into high speed steel HS10-4-3-10 in a H3PO4-environment and compared to those of the self-passivating cobalt-chrome alloy Stellite 21. As a result, the laser-induced removal velocities in HS10-4-3-10 amount to 50 μm/s. These are two orders of magnitudes higher than the background etching (2 nm/s at room temperature) and three times higher than those obtained in Stellite 21 (12 μm/s). However, the microscopic and spectroscopic analyses of both materials reveal a high shape accuracy with edge radii from 10 to 20 μm, a surface roughness down to 0.8 μm and a negligible microstructural impact. Despite lower removal rates and higher surface roughness, laser chemical machining provides higher dimensional accuracy in comparison with micro milling and shows its suitability for micro machining of structures <200 μm.

show abstract

Section: Influence Of Self-passivation Property On the Machining Qualitysupporting

confidence: 75%

Removal behavior and output quality for laser chemical machining of tool steels

et al. 2019

View full text Add to dashboard Cite

show abstract

“…The LCM-induced surface irregularities are related to two different effects. The first one is due to the used Gaussian laser beam profile, which results in an inhomogeneous removal even with closed hatching distance [21]. The second effect is related to the unequal chemical dissolution rates of the different alloy elements with respect to the used electrolyte solution [22] as well as the dependence of the achievable surface quality on the micro structure (grain size and element distribution) [15].…”

Section: Discussionmentioning

confidence: 99%

Chances and Limitations in the Application of Laser Chemical Machining for the Manufacture of Micro Forming Dies

et al. 2018

Self Cite

View full text Add to dashboard Cite

Laser chemical machining, a non-conventional processing method based on thermally activated electrochemical material dissolution, represents a promising technology for manufacturing metallic dies for micro forming applications. Prior to widespread industrial acceptance the machining quality of laser chemical machining should be characterized. For this purpose, laser chemical machining is compared with micro milling regarding both the dimensional accuracy and the surface quality. Therefore, square micro cavities exhibiting side walls between 100 μm and 400 μm in length and 60 μm in depth are machined with both manufacturing processes into the cobalt-chrome alloy Stellite 21. The geometrical features are investigated using laser-scanning confocal microscopy and scanning electron microscopy. On the one hand, laser chemical machining is more suitable for manufacturing cavities with dimensions < 200 μm due to higher shape accuracy with stable mean edge radii of (11.2 ± 1.3) μm as a result of roughing and finishing steps. On the other hand, the finish quality of micro milling with mean surface roughness Sa of 0.2 μm could not be achieved with laser chemical machining due to in-process induced waviness. Finally, the metallographic analysis of the surface-near layers reveals that both manufacturing processes ensure gentle machining without any noticeable micro structural impact.

show abstract

“…These ensure the highest efficiency, as was demonstrated by Nowak et al [Now96] and Stephen et al [Ste11]. However, more environmentally friendly electrolytes such as sodium chloride (NaCl) and sodium nitrate (NaNO 3 ) solutions were tested and compared with the acidic solutions [Hau15a]. The results will be discussed in more detail in Sect.…”

Section: Influence Of the Electrolytementioning

confidence: 91%

“…Thereby, the amount and quality of the material dissolution is dependent on the chemical reactivity of the material elements. In [Hau15a] it was shown that the LCM of titanium in a 5 molar H 3 PO 4 results in up to 39% higher removal rates and up to 30% deeper cavities in comparison with Stellite 21. This can be explained by the higher electronegativities of cobalt (63%) and chromium (25%), as the main elements in Stellite 21, in comparison with that of titanium.…”

Section: Influence Of the Materialsmentioning

confidence: 99%

See 1 more Smart Citation

Tooling

Vollertsen

Seven

Messaoudi

et al. 2019

Lecture Notes in Production Engineering

Self Cite

View full text Add to dashboard Cite

Micro metal parts are usually produced in large lot sizes at high production rates. In order to achieve sufficient product quality, excessive tool wear has to be avoided. In the micro range, so-called scaling effects and their influence on tool wear in micro forming have not been investigated so far. For the investigation, tests in micro deep drawing were carried out with metal sheets (s < 50 μm) of pure aluminum Al99.5, a copper alloy E-Cu58 and stainless steel 1.4301. The failure mechanisms of the micro cups produced were identified as bottom fracture and cup wall damage, and tool wear was measured and characterized with optical measurements and EDX analyses. Moreover, micro cups can be produced by DLC-and PVD-coated tools in a dry forming process. To investigate the wear behavior in a continuous process, a forming tool was developed with an integrated blanking and deep drawing die. The tool wear was measured optically, and the wear mechanisms could be identified in a combined micro and deep drawing process. As a result, the tool could be modified by a manufacturing in selective laser melting and the tool life increased by 290%. Furthermore, a method for tool wear examination in long-term tests was developed. In lateral micro upsetting, the tool wear history can be examined by analyzing the formed product. Several tool materials and coatings were tested with up to 500,000 strokes.

show abstract

Electrolytes for Sustainable Laser-Chemical Machining of Titanium, Stellite 21 and Tool Steel X110CrMoV8-2

Cited by 3 publications

References 10 publications

Removal behavior and output quality for laser chemical machining of tool steels

Removal behavior and output quality for laser chemical machining of tool steels

Chances and Limitations in the Application of Laser Chemical Machining for the Manufacture of Micro Forming Dies

Tooling

Contact Info

Product

Resources

About