Classifications

• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C9/00—Alloys based on copper
  • C22C9/05—Alloys based on copper with manganese as the next major constituent
• • C—CHEMISTRY; METALLURGY
  • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
  • C22C—ALLOYS
  • C22C9/00—Alloys based on copper
  • C22C9/01—Alloys based on copper with aluminium as the next major constituent

Definitions

• the invention relates essentially to nickel-free non-ferrous metal alloys and their use as a material for jewelry and metal objects that come into contact with human skin during normal use, in particular spectacle frames and parts of spectacle frames.
• Nickel-containing materials are used to manufacture eye wires and other parts for eyeglass frames. Examples are the non-ferrous metal alloys listed in Table 1 with corresponding material numbers according to DIN and compositions: Table 1 Non-ferrous metal alloys according to DIN Material number. alloy DIN 2.0730 CuNi 12 Zn 24 17663 2.0740 CuNi 18 Zn 20 17663 2.0842 CuNi 44 Mn 1 17664 2.4110 NiMn 2 17741 2.4360 NiCu 30 Fe 17743 2.4361 LC-NiCu 30 Fe 17743 2.4870 NiCr 10 17742/73
• the invention is therefore based on the object of providing a material for jewelry and metal objects which come into contact with human skin in normal use and in which the problem of possible allergic reactions does not occur.
• a nickel-free or essentially nickel-free non-ferrous metal alloy with the following composition in percent by weight: Mn: more than 5.0 to 15.00% Al: 4.0 to 7.50% Fe: 1.0 to 2.80% B: 0.0005 to 0.01% Si: 0.0 to 0.30% Ni: 0.0 to 0.09% C: 0.0 to 0.08% S: 0.0 to 0.03% P: 0.0 to ⁇ 0.01% and copper with remnants of melting-related impurities.
• the alloy can be produced by conventional metallurgical processes.
• the material and objects made from it e.g. Glasses and parts of glasses do not cause a nickel allergic reaction if they come into contact with human skin for a long time.
• This essential condition is met according to the invention by the non-ferrous metal alloy according to claim 1, which is free of nickel up to a maximum of 0.09%.
• Table 2 shows the nickel emissions of alloys according to the invention determined in the corrosion test.
• the alloy according to the invention can be used as a material for the production of jewelry and metal objects which are in contact with the skin under normal use. Examples include earrings and ear studs, necklaces, bracelets and chains, anklets, finger rings, hair clips, watch bottoms, watch straps, chains and clips, buttons, clips, rivets, zippers and metal pendants.
• the alloy according to the invention is also advantageous for coins.
• the non-ferrous metal alloy according to the invention is particularly suitable for spectacle frames and parts of spectacle frames.
• Materials for eyeglass frames or parts thereof are solidified by cold forming during manufacture. This requires good cold formability. This requirement is met according to the invention in that a homogeneous, in particular single-phase, copper mixed crystal alloy is used due to its chemical composition. Examples of alloys according to the invention are listed in Table 2.
• the individual parts are connected to one another.
• Such individual parts are connected, inter alia, by means of welding, preferably resistance welding, but also by other methods which introduce very small amounts of heat into the parts to be connected.
• the connection can also be carried out by soldering, preferably hard, resistance or high-frequency soldering.
• the connections can also be glued.
• the eyeglass frames or eyeglass frame parts are subjected to various surface treatments and / or provided with coatings with nickel-free metallic and non-metallic substances.
• a coating serves to improve the protection of the alloy against atmospheric corrosion and / or to improve the appearance; on the other hand, the coating is not used to protect human skin from nickel-allergic reactions.
• the surface treatment includes to name polishing and electroplating.
• the alloys according to the invention meet the requirement of galvanizing and polishing ability.
• Manganese additives in the alloys which can be used according to the invention increase the strength properties by solid-solution strengthening both at room temperature and at higher temperatures. Furthermore, they improve the aforementioned cold formability, in particular the homogeneous alpha copper alloys. Manganese additives noticeably improve the weldability.
• connection work in particular various soldering and welding processes, can be carried out and so the strength achieved by cold working is largely retained even after these connection work.
• the metallurgical explanation of only a slight reduction in strength in the heat-affected area of a soldering of cold-worked non-ferrous non-ferrous alloys according to the invention lies in the small temperature difference, ie only a small thermal activation as the driving force of the primary recrystallization, between the working temperature of the soldering process and the high recrystallization temperature of the alloy used.
• the sulfur content is limited to a maximum of 0.03%, while the phosphorus content should be less than 0.01%, since higher contents in mixed copper-crystal alloys lead to hot brittleness and, in particular, significantly impair the required weldability.
• boron in contents of 0.0005 to 0.01% to homogeneous alpha-copper mixed crystal alloys has an advantageous effect in a noticeable improvement in the hot deformability or reduction in the hot brittleness. Furthermore, boron promotes fine grain, which in turn has a positive effect on the cold-forming ability. A limitation to a maximum of 0.010% is intended to avoid the occurrence of undesirable boron deposits.
• the nickel release of the alloys according to the invention is below the required limit of 0.5 ⁇ g per cm2 and per week and is significantly less than the nickel release of the comparison alloy.
• Table 2 Chemical composition of the test alloys 1 to 4 and the comparative alloy 5 in percent by weight and their nickel release determined in the corrosion test in ⁇ g per cm2 and per week: alloy 1 2nd 3rd 4th 5 Mn 5.3 9.2 9.8 14.6 1.1 Al 7.2 6.0 6.1 4.9 0.4 Fe 2.4 1.8 2.1 1.2 2.1 Si 0.07 0.15 0.01 0.05 0.10 Ni 0.14 0.02 0.03 0.01 rest C.

Landscapes

• Chemical & Material Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Mechanical Engineering (AREA)
• Metallurgy (AREA)
• Organic Chemistry (AREA)
• Eyeglasses (AREA)
• Manufacture And Refinement Of Metals (AREA)

Applications Claiming Priority (2)

Publications (2)

Family

ID=6457874

Family Applications (1)

Country Status (3)

Cited By (6)

Citations (5)

Family Cites Families (7)

• 1992
  • 1992-04-30 DE DE4214304A patent/DE4214304A1/de not_active Withdrawn
• 1993
  • 1993-04-30 EP EP93107068A patent/EP0568094B1/fr not_active Expired - Lifetime
  • 1993-04-30 AT AT93107068T patent/ATE157125T1/de not_active IP Right Cessation
  • 1993-04-30 DE DE59307143T patent/DE59307143D1/de not_active Expired - Fee Related

Patent Citations (5)

Also Published As

Similar Documents

Legal Events