1. A method for manufacturing a gold alloy product, the method comprising;
casting an ingot of a composition comprising (in wt%):
gold (Au) 90.0% to 92.0%,
5 copper (Cu) 6.0% to 6.5%,
silver (Ag) 1.4% to 1.6%,
combined composition of nickel (Ni) and gallium (Ga) 0.45% to 0.75%,
and
the balance being incidental elements and impurities;
10 subjecting, the ingot to a first rolling process for reducing thickness to a first
predetermined thickness;
subjecting, the rolled ingot to a first annealing process at a first predetermined
temperature;
quenching, the annealed ingot to a second predetermined temperature;
15 subjecting, the quench-annealed ingot to a second rolling process to a second
predetermined thickness to form a strip;
subjecting, the strip to a second annealing process at a third predetermined
temperature;
cooling, the annealed strip at a predetermined cooling rate to form the gold
20 alloy product, wherein the gold alloy product exhibits a load bearing capacity of 3.5 kgf
to 5.5 kgf.
2. The method as claimed in claim 1, wherein the casting of the ingot is performed at a
temperature range of 1075 ℃ to 1125 ℃ for time ranging from 20 minutes to 30
minutes.
25
3. The method as claimed in claim 1, wherein the first rolling process is a rough rolling
process for reducing thickness of the ingot to the first predetermined thickness ranges
from 7 mm to 9 mm.
30 4. The method as claimed in claim 1, wherein the first annealing includes subjecting the
rolled ingot to a first predetermined temperature ranging from 600℃ to 700℃ for a
time ranging from 25 minutes to 35 minutes.
17
5. The method as claimed in claim 1, wherein the annealed ingot is quenched to the second
predetermined temperature, wherein the second predetermined temperature is the room
temperature.
5 6. The method as claimed in claim 1, wherein the second rolling process reduces thickness
of the ingot to the second predetermined thickness ranges from 2 mm to 4 mm to form
the strip.
7. The method as claimed in claim 1, wherein the second annealing treatment includes
10 annealing, the rolled strip at the third predetermined temperature ranging from 700℃
to 800℃ on a continuous belt running at 70 RPM to 90 RPM.
8. The method as claimed in claim 1, wherein the predetermined cooling rate is 1.2°C/s to
1.8°C/s.
15
9. The method as claimed in claim 1, wherein the hardness of the casted gold 85 HV5kgf
to 95 HV5kgf.
10. A gold alloy product, comprising:
20 a composition in weight percentage (wt%) of:
gold (Au) 90.0% to 92.0%,
copper (Cu) 6.0% to 6.5%,
silver (Ag) 1.4% to 1.6%,
combined composition of nickel (Ni) and gallium (Ga) 0.45% to 0.75%,
25 and
the balance being incidental elements and impurities;
wherein, the gold alloy product exhibits a load bearing capacity of 3.5 kgf to
5.5 kgf