You will need
- Accurate scales and a transparent graduated container with water; a calculator; a strong magnifier or a microscope, samples of bronze and brass chipped.
Instruction
1
Start with visual analysis. You must thoroughly clean the item and place into the sunlight. As a rule, the darker bronze of brass, and, if you evaluate the color, the bronze goes into the "red" spectrum (i.e. from reddish to brown) and brass in yellow up to white. However, this method is extremely inaccurate, so proceed to the next step.
2
Analyze the alloy density. You will need accurate scales and a transparent, graduated container with water. Lowering of the object in water is determined by its volume, weighing a lot. Density is the ratio of body mass to its volume, and transfer format C (kg/ cubic meter). Typically, bronze is denser than brass, and the dividing line lies at the value of 8700 kg/cu. m. 8400 – 8700 kg/cubic meter – almost certainly brass. 8750 – 8900 – almost certainly bronze.
3
Finally, the structure of the alloy. It should be noted that what is needed are samples of items which can be uniquely identified as bronze and brass; the samples must be chipped.
For the actual analysis will need a strong (preferably binocular) microscope or magnifying glass (even children). The analysis is placed in view at the same time sample (cleavage) and the object of analysis. What we should look for? On the structure of the alloy – as they say, his "grain". Generally, bronze is larger and more coarse grain than the brass.
For the actual analysis will need a strong (preferably binocular) microscope or magnifying glass (even children). The analysis is placed in view at the same time sample (cleavage) and the object of analysis. What we should look for? On the structure of the alloy – as they say, his "grain". Generally, bronze is larger and more coarse grain than the brass.
Note
Bronze and brass are alloys based on copper (about 90%).
Typically, the main alloying element in bronze is tin, for brass – zinc. This is in principle true for the alloys made before the beginning of the 1980s (that is, the task was limited to the identification of zinc in the alloy). Later, however, the zinc began to enter into the composition of bronze, so the measurement is now based on complicated methods of determining the percentage of elements in the alloy, which is practically impossible at home.
Typically, the main alloying element in bronze is tin, for brass – zinc. This is in principle true for the alloys made before the beginning of the 1980s (that is, the task was limited to the identification of zinc in the alloy). Later, however, the zinc began to enter into the composition of bronze, so the measurement is now based on complicated methods of determining the percentage of elements in the alloy, which is practically impossible at home.