Bronze is a prized metal alloy for sculptors and other artisans.
Bronze, an alloy of copper and tin, is neither brittle like tin nor quite as soft as copper. Most bronze is used today for hammers, wrenches and mallets in areas containing flammable vapors and high explosives because it does not generate sparks when colliding with hard surfaces. Many sculptors still choose bronze because it picks up fine details when cast and shrinks when set, making it easy to remove from casts. Bronze, however, does have a few disadvantages.
Expense
Bronze is more expensive than brass and steel but less than nickel-base alloys. This is due primarily to its copper content. Pete Bowie, a bronze sculpture artist, says that the silicone bronze that he uses has a content composed of 95 percent copper, and in the last few years the price of copper has risen 500 percent from $.75 to $3.50 per pound.
Deterioration
Bronze has poor resistance to ammonia and ferric compounds and cyanides. Dirt and dust can also eat into its surface. Acid in bird droppings and concentrations of chemical agents in animal excretion also aids in corrosion and deterioration in sheltered areas of bronze works. A combination of sulphur and chlorine in a moist atmosphere is the most significant causes of deterioration.
Core Migration
When a bronze piece is cast in a mold, it has a non-bronze core usually made of plaster-of-paris or gypsum. Sometimes these cores are left in place accidentally. This material then makes its way through the bronze and in time finds its way to the surface, manifesting as tiny white spots which enlarge over time and must be removed by bronze restoration experts.
Disease
A sudden appearance of small areas of light green, rough spots on a piece of bronze indicates the presence of Bronze Disease. This disease, equivalent to rust in iron-based metals, occurs when oxygen and chloride combine in a moist environment to make hydrochloric acid. This acid forms copper and tin chlorides which in turn break down the bronze. Uncontrolled, this process will eventually destroy the bronze.
Soft Metal
Because of its softness, bronze does not make sturdy weapons. It also cannot hold an edge well. During the Bronze Age, bronze swords were used primarily for stabbing but even then tips would bend on impact and require straightening.
Weight
Although bronze is lighter than steel by about 10 percent, comparing bronze to iron and other metals depends on the composition of the materials used to make the bronze. Case in point, bronze containing 8 to 14 percent tin runs from 7400 to 8900 kilograms per cubic meter while iron is 7850 kilograms per cubic meter.
Related posts
Easier to install and less expensive, drywall has overtaken plaster in popularity.When you build or remodel a home, you have many decisions to make. Some, like paint color and curtain fabric, are...
Partition walls in offices offer versatility.Partition walls have many uses in the office, home or in schools. They create privacy and personal work spaces. They can divide classrooms or groups of...
Plaster application requires extensive training.Plaster was once the most common form of interior wall finishing, but this changed when the pressed gypsum boards known as drywall became widely ava...
Advantages & Disadvantages of XRD and XRFXRF and XRD are two common x-ray techniques. Each has advantages and disadvantages to its specific method of scanning and measuring. Though these techn...
Wall insulation systems help to keep homes more energy-efficient and comfortable. According to Energy Saving Trust, "If your home was built from 1920 onwards, the chances are that its externa...
