Whether being used for jewellery, a catalytic converter or for an alloy wheel, most platinum alloys contain a maximum of 5% additional materials. A very few contain between 5-10% extra metals. The reason for this is simple; it is these proportions that produce the desired properties of durability, toughness and resistant to wear and tear. To be able to cope with alloy wheel refurbs or repair, and the stresses produced by normal usage, most platinum alloys contain a minimum of 95% to 99% by mass of Platinum. In addition, many of the different types of platinum alloy are manufactured under patent and exceptionally strict standards. Some of the metals added to platinum are tin, zirconium, indium, titanium and gallium. These are the five most common platinum alloys used in the automotive industry:
1) Platinum-tin alloy:
The addition of between 1% and 6% tin to a given mass of platinum results in a steady increase in hardness; provided the liquid metal was heated to 1000°C. From this position, the characteristics of the alloy can be altered by altering the rate of cooling and or percentage of tin added to the metal. For instance, if the percentage of tin added is increased to 3%, equivalent properties of hardness to an alloy containing less tin can be produced, if the temperature of the liquid alloy does not exceed 800°C.
2) Platinum-zirconium alloy:
As with tin, the hardest alloys are produced at a temperature of 1000°C +, but the proportion of added zirconium ranges from between 1% and 5%. If the percentage of zirconium is kept between 3% and 4 % and the maximum temperature does not exceed 800°C, less durable alloys are produced. This trend continues as the variables of temperature; platinum and alloy are altered.
3) Platinum-indium alloy:
A temperature of 1000°C and the addition of between 1% and 7% added indium produces the hardest platinum alloys. However, in this case there is no dramatic change in hardness when the temperature is not allowed to exceed 800°C. Research suggests that at between 800°C to 1000°C the optimum addition of indium is 6.9% of mass of platinum.
4) Platinum-titanium alloy:
Here the relationship between temperature and percentage alloy is more complex and the rate of cooling is more of a crucial determinant of the final properties of the alloy. At 1000°C the optimum mix is between 1% and 5% titanium. However, at 1000°C, the more titanium added, the less durable the alloy, such that 2% titanium produces the hardest alloy. A similar trend is observed at 800°C, but in all cases the alloy was less hard than its 1000°C equivalent.
5) Platinum-gallium alloy:
At 1000°C, an addition of between 1% and 6% gallium produces a very tough and durable alloy, with an increased percentage providing the hardest substance. At 800°C, the optimum range of added gallium is between 3.8% and 6%, per given mass of platinum. For this alloy, purity is a definite factor; the less pure each element is, the less hard the alloy. For this alloy, the metals are subject to electrolysis or equivalent processes to obtain metals of a high enough grade.
The above range of alloys is by no means an exhaustive list. There are hundreds of different platinum alloys, and this number increases continually. In many cases, more than one additional metal can be added which further changes the properties of the final alloy. Overall it is the relationship between temperature and proportion that produces a given set of properties and manufacturing processes trade-off between these two variables.
http://www.platinumwheelrefurb.com/
1) Platinum-tin alloy:
The addition of between 1% and 6% tin to a given mass of platinum results in a steady increase in hardness; provided the liquid metal was heated to 1000°C. From this position, the characteristics of the alloy can be altered by altering the rate of cooling and or percentage of tin added to the metal. For instance, if the percentage of tin added is increased to 3%, equivalent properties of hardness to an alloy containing less tin can be produced, if the temperature of the liquid alloy does not exceed 800°C.
2) Platinum-zirconium alloy:
As with tin, the hardest alloys are produced at a temperature of 1000°C +, but the proportion of added zirconium ranges from between 1% and 5%. If the percentage of zirconium is kept between 3% and 4 % and the maximum temperature does not exceed 800°C, less durable alloys are produced. This trend continues as the variables of temperature; platinum and alloy are altered.
3) Platinum-indium alloy:
A temperature of 1000°C and the addition of between 1% and 7% added indium produces the hardest platinum alloys. However, in this case there is no dramatic change in hardness when the temperature is not allowed to exceed 800°C. Research suggests that at between 800°C to 1000°C the optimum addition of indium is 6.9% of mass of platinum.
4) Platinum-titanium alloy:
Here the relationship between temperature and percentage alloy is more complex and the rate of cooling is more of a crucial determinant of the final properties of the alloy. At 1000°C the optimum mix is between 1% and 5% titanium. However, at 1000°C, the more titanium added, the less durable the alloy, such that 2% titanium produces the hardest alloy. A similar trend is observed at 800°C, but in all cases the alloy was less hard than its 1000°C equivalent.
5) Platinum-gallium alloy:
At 1000°C, an addition of between 1% and 6% gallium produces a very tough and durable alloy, with an increased percentage providing the hardest substance. At 800°C, the optimum range of added gallium is between 3.8% and 6%, per given mass of platinum. For this alloy, purity is a definite factor; the less pure each element is, the less hard the alloy. For this alloy, the metals are subject to electrolysis or equivalent processes to obtain metals of a high enough grade.
The above range of alloys is by no means an exhaustive list. There are hundreds of different platinum alloys, and this number increases continually. In many cases, more than one additional metal can be added which further changes the properties of the final alloy. Overall it is the relationship between temperature and proportion that produces a given set of properties and manufacturing processes trade-off between these two variables.
http://www.platinumwheelrefurb.com/