BS EN ISO 28319:2018 pdf download – Dentistry – Laser welding and filler materials (ISO 28319:2018)
This document specifies requirements and test methods for laser welding and the filler materialsthereto used in the dental laboratory for welding of metallic restorations and appliances.
For filler materials used in laser welding, this document also specifies the information given in theinstructions for use, marking and labelling.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their contentconstitutes requirements of this document. For dated references, only the edition cited applies. Forundated references, the latest edition of the referenced document (including any amendments) applies.
ISO 1942, Dentistry — Vocabulary
ISO 6344-1, Coated abrasives — Grain size analysis — Part 1: Grain size distribution test
ISO 10271:2011, Dentistry — Corrosion test methods for metallic materials
ISO 15223-1:2016, Medical devices — Symbols to be used with medical device labels, labelling and
information to be supplied — Part 1: General requirements
ISO 22674:2016, Dentistry — Metallic materials for fixed and removable restorations and appliances
3 Terms and definitions
For the purposes of this document, the terms and definitions given in ISO 1942, ISO 22674 and thefollowing apply.
ISO and IEC maintain terminological databases for use in standardization at the following addresses:
— IEC Electropedia: available at http://www.electropedia.org/
— ISO Online browsing platform: available at https://www.iso.org/obp
3.1
laser welding
method for joining similar or dissimilar metallic materials, using a laser beam as the heat source, withor without a metallic filler material (welding rod), which produces coalescence by melting abuttingzones of metallic material components thereby creating a common fusion zone
3.2
filler material
<laser welding> metallic filling material used for laser welding (3.1)
4.4 Corrosion resistance
4.4.1 Static immersion test When pieces of a single metallic material are joined, the metal ion release shall not exceed 200 μg cm −2 in a time period of 7 d ± 1 h. The metallic materials to be joined and the laser welded specimens shall conform to ISO 22674:2016, 5.7. Testing shall be carried out in accordance with 7.4.
4.4.2 Appearance after corrosion exposure Magnified visual comparison prior to and after corrosion testing shall not reveal any visible selective corrosion in the vicinity of the laser weld. Testing shall be carried out in accordance with 7.4.
4.5 Laser welding process Specific information about the laser welding process is given in Annex A. 5 Sampling The metallic filler material and the metallic material each shall be from one lot. It shall be sufficient to prepare the specimens as required in 6.1 and 6.2 including provision for a second set for tensile testing. Further samples and packaging materials shall be made available for inspection in accordance with 9.2. If the proof strength values of 0,2 % non-proportional extension of the one or two metallic materials to be joined by laser welding are available from a test report according to ISO 22674, these data can be used. If not, perform the tests according to ISO 22674 to determine the required values of proof strength of 0,2 % non-proportional extension.
6 Preparation of specimens 6.1 General The specimens consist of the metallic materials joined by laser welding either with or without using a filler material according to the instructions for use. For casting alloys to be tested prepare the test specimens by the “lost wax process” of investment casting. Methods other than casting may be recommended by the manufacturer for the metallic material to be tested for suitability for laser welding. Use such a method, if recommended by the manufacturer. Follow the instruction for use relating to the processing of the metallic material(s) and if applicable the filler material including the use of necessary aids and casting and welding equipment.
Specimens with visible defects shall be discarded and replaced. Specimens shall be separated fromsprues, casting beads/runners, fins and other projections. Surface contaminations shall be removed.
The specimens shall be in the metallurgical state(s) appropriate to their intended application(s).
If a heat-treatment is recommended by the manufacturer, perform the tests in the heat-treated state inaccordance with the instruction for use.
If laser welding is recommended following ceramic firing, the simulated ceramic firing of the specimensshall be in accordance with ISO 22674:2016, 7.2.3, and shall be applied before laser welding.BS EN ISO 28319 pdf download.