1 Not all adenomas produce excess T-4, and doctors aren't sure what causes some to begin producing too much hormone. 2  Thyroiditis. 3  Sometimes your thyroid gland can become inflamed for unknown reasons. 4  The inflammation can cause excess thyroid hormone stored in the gland to leak into your bloodstream.
Forged steel is an alloy of carbon and iron that is compressed under extreme pressure to make a very hard and strong substance. It has been used for thousands of years to create all types of materials.
Steel is an alloy because it is a mixture of a metal (iron) with other elements (carbon and perhaps other metals too). Iron from the blast furnace contains about ~96% iron with ~4% of impurities including carbon, silica and phosphorus.In this state the cast iron is too hard and too brittle for most purposes.aCO3. 1  Iron ore is used to make iron and steel eg haematite and magnetite. 2  Iron is produced (extracted) in a blast furnace by reducing iron oxides with carbon and it is the carbon that removes the oxygen from the iron oxides the carbon is known as the reducing agent.