Carpenter Technology Corporation develops, manufactures and distributes stainless steels and special corrosion-resistant alloys, primarily for use in the aerospace, industrial, energy, transportation, and medical industries.

The company's revenues in fiscal year 2016 were derived from the following industries:

The company was founded by James Henry Carpenter and a small group of New York City investors on June 1, 1889 as the Carpenter Steel Company. He envisioned methods to improve the process of steelmaking.

In May 1890, the company received a contract from the United States Secretary of the Navy to develop armor-piercing projectiles. James Carpenter had received a patent for an "air-hardening steel" manufacturing process. In November 1896, the Navy referred to the company's projectiles as "the first made that would pierce improved armor plate." In the Spanish–American War of 1898, the routing of the Spanish fleet at Manila Bay was credited in part to projectiles made by Carpenter.

The burgeoning automobile industry of the early 20th century led to several advancements at the company. In 1905, the company developed a prime grade chrome-nickel steel and by 1908 it had created ten other steels that were used to make automobile chassis. Most of the "runabout" vehicles of the day ran on Carpenter steel, and "Old 16," the race car that won the Vanderbilt Cup in 1908, comprised front and rear axles, crankshaft, gears, and other parts fabricated from Carpenter steel.

In 1903, Carpenter's "special" steels were used in the engine of the Wright brothers' maiden flight.

After the United States entered World War I, munitions and supplies became the company's top product.The Reading plant operated on 24-hour shifts, producing everything from tool steels to soldiers' safety razor blades.During the war, the company put into operation 4 new electric-arc furnaces, which allowed greater control over the melting process than the old crucible furnaces. In December 1917, the company manufactured its first high-strength, chemical-resistant stainless steel which was immediately used in airplane engine components, cutlery, and spark plugs.

In December 1920, Carpenter unveiled its "rustless steel," an alloy of 0.3% carbon, 20% chromium, and 1% copper. In 1927, Carpenter's Welded Alloy Tube Division became the earliest commercial supplier of stainless tubing, with applications in chemical processing, oil refining, generation of electricity, and food and beverage processing. In 1928, it introduced the first free-machining, "antifriction" stainless steel, due to use of sulfur. In 1929, the company produced 24 pounds of automotive trim on each Pierce Arrow car.

The gears, shafts, and fasteners of the engine of the "Spirit of St. Louis," Charles Lindbergh's legendary plane that flew across the Atlantic Ocean in May 1927, were all made from Carpenter steel. An identical engine had powered Richard E. Byrd's flight to the North Pole in 1926.

Although the company operated at a loss during the Great Depression, the company introduced new stainless steels with additives of selenium, tellurium, and chrome and nickel and began licensing other manufacturers to produce some of its stainless steels.

In June 1937, Carpenter Steel Company became a public company via an initial public offering.

In March 1941, with U.S. entrance into World War II looking increasingly probable, the U.S. Office of Production Management summoned Carpenter's president to Washington, D.C., to discuss expanding the company's production capacity on urgently. Carpenter's board of directors voted to immediately implement a capital investment program of nearly $1 million. During the war, the company's stainless steel was used in engine parts, steel fasteners, and cockpit instruments for fighter planes and bombers; components of Sherman tanks and submarines; radio masts for PT boats and radio equipment for battle fronts; and medical supplies such as hypodermic needles and surgical implements.

During the 1950s, Carpenter introduced "Stainless 20," an alloy which by virtue of rare earth element additives could withstand harsh, corrosive chemicals. In 1951, Carpenter bought a wire redrawing plant in New Jersey, which produced fine wire for applications such as surgical sutures and knitting machines. In 1954, the company added a new mill in Reading which allowed Carpenter to become extremely competitive in the manufacture of specialty alloy wire. After the company had to turn down orders due to not having enough capacity, Carpenter acquired Northeastern Steel Corporation in Bridgeport, Connecticut, enabling a 100% increase in the production of ingots.

The company made the following acquisitions in the 1960s: NTH Products, Inc., of El Cajon, California, in 1961; a 50 percent share in Gardner Cryogenics Corporation, Bethlehem, Pennsylvania, in 1969; and a 50 percent share in Titanium Technology Corporation, Pomona, California, also in 1969. In 1967, the company opened a new research and development center. In 1968, the company changed its name to Carpenter Technology Corporation to reflect its research and development initiatives.

In the 1970s, Carpenter sold the New Jersey wire redrawing plant, Titanium Technology Corporation, Gardner Cryogenics, and affiliates in Brazil and Mexico. According to Howard O. Beaver, Jr., who was then president, the divested enterprises "did not fit Carpenter's long-range goals and objectives".

In the 1980s, Carpenter acquired Eagle Precision Metals Corporation of Fryeburg, Maine, a precision drilling facility that produced high quality hollow steel bars, and AMAX Specialty Metals Corporation of Orangeburg, South Carolina, a wire-finishing plant, capable of redrawing steel wire to extremely fine sizes.

In September 1986, 498 employees of the company participated in a strike action. The strike ended in December 1986.

Carpenter received a patent in 1992 for super-strong Aermet alloy, first used for the landing gear on aircraft carrier-based jet fighters. AerMet 100 was named one of the top material advances of the decade by the National Association for Science, Technology and Society.

In 1993, Carpenter developed the Carpenter CTS family of 14 alloys to assist knife blade designers in alloy selection.

In January 1997, Carpenter acquired Dynamet a titanium alloy producer based in Washington, Pennsylvania, for $161 million.

In September 1997, the company acquired Talley Industries for $185 million.

In July 1998, the company sold John J. McMullen Associates Inc. and Waterbury Companies.

In October 1998, the company announced a $113.6 million investment to expand its Pennsylvania melt shop.

In 2009, Carpenter began supplying its cobalt-based BioBlu 27 alloy into the jewelry industry. In 2010, Carpenter developed ACUBE 100 alloy, a beryllium-free material for bushings and bearings. Also in 2010, Carpenter launched PremoMet alloy to consider for high demand diesel engine components.

In 2011, the company acquired Amega West Services for $54 million, which expanded its business in the oil and gas drilling market.

In 2012, the company announced plans to construct a manufacturing facility in China.

In 2015, Tony R. Thene was named president and chief executive officer of the company.

On June 18, 2002, five plaintiffs filed a suit against Carpenter Technology to recover costs that had been paid to the United States Environmental Protection Agency to cleanup the Boarhead Farms Superfund Site in Bucks County, Pennsylvania. A settlement of $21,800,000 was reached in 2011.

The company released more than 1.2 million pounds of toxic chemical waste into the Schuylkill River and was the fourth-largest polluter of toxic chemicals in Pennsylvania in 2007; however, it is not clear whether the discharge amounts were within the allowed federal permit limits.

James Henry Carpenter in 1861 or 1862 in the Union Navy at about age 15.

James Henry Carpenter, about 1895, founder of Carpenter Steel Company, now Carpenter Technology Corporation.

Carpenter Steel Company Plant in 1893, Reading, Pa, looking east.

The Carpenter Steel Company Plant, now called Carpenter Technology Corporation about 2010, looking north.

Carpenter Steel Company projectile test on steel plate circa early 1890s.

Carpenter Steel Company in the 1890s pouring steel into crucibles.

Carpenter Steel Company in the 1890s showing a rolling mill.

Full picture: James Henry Carpenter in 1861 or 1862 in the Union Navy at about age 15.