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.
How to Harden Steel. Steel is an alloy of iron used in construction, the manufacture of metal tools and other applications. In uses exposing it to a lot of wear and tear, the steel must be hardened and then tempered so it stands up to the level of usage it's intended for.