Modern industry knows many complex metal alloys, but perhaps the oldest and most widespread is bronze: an alloy of copper with tin, beryllium, chromium, aluminum. This alloy is used not only in production, but also in artistic craft. Craftsmen make statuettes, adornments, and chasing out of malleable bronze.
Instructions
Step 1
To determine bronze means to find out the composition of the alloy that you have in your hands. For those who work with bronze, a superficial examination is sufficient. Clean the item from dust and corrosive oxides. Then go to the examination with a regular or binocular loupe, but choose the right lighting. Do a trial macroscopic mechanical trim with a scalpel or sharp knife.
Already by the color of this cut, you can determine which alloy in front of you. Depending on the composition, bronze has a different color. If bronze contains 90% copper, then it is red, if copper is 85%, then the alloy becomes yellow, if 50% is white, 35% is steel gray.
Alloys of copper with beryllium are bright red, and with aluminum they have a pastel shade, and sometimes sinewy blotches.
Step 2
For a more accurate analysis, conduct a chemical study using reagents. Place 0.05 g of the alloy in the form of sawdust or shavings in a beaker, add 10 ml of nitric acid, which was previously diluted with water in a 1: 1 ratio, cover the beaker with a glass. After more of the alloy has dissolved, heat the liquid in a water bath to almost boiling and soak it hot for 30 minutes. If, after this experiment, a white precipitate appears at the bottom of the beaker, then the product is made of bronze.
Step 3
In an industrial environment, use a spectrometer. This device, based on the available parameters of the physical properties of the metal, as well as its particles (for example, scraping), conducts a study on its components.
Step 4
In laboratory conditions, it is possible to carry out a photometric analysis based on the interaction of lead diethyldithiocarbamate in chloroform with copper ions in an acidic medium, resulting in the formation of copper diethyldithiocarbamate. The uninitiated can understand the essence of the reaction by changing the color of the liquid in the test tube with the test material - in the presence of a bronze alloy, the content turns yellow-brown.
