Physical metallurgy

Physical metallurgy is one of the two main branches of the scientific approach to metallurgy, which considers in a systematic way the physical properties of metals and alloys. It is basically the fundamentals and applications of the theory of phase transformations in metal and alloys.^[1] While chemical metallurgy involves the domain of reduction/oxidation of metals, physical metallurgy deals mainly with mechanical and magnetic/electric/thermal properties of metals – as described by solid-state physics.

Early history

An iron-carbon phase diagram showing the conditions necessary to form different phases

Timeline:^[2]

• 1831 – Pavel Petrovich Anosov looks at metals in a microscope.
• 1841 – Anosov finds the secret to Damascus steel.
• 1868 – Dmitry Chernov founds physical metallurgy. He identifies the critical points of steel.
• 1875 – William Chandler Roberts-Austen provides the diagram Ag-Cu.
• 1878 – Adolf Martens describes relations between microstructure and physical properties, specially the role of kinks, defects and crystallization.
• 1887 – Henry Clifton Sorby determines the pearlite structure.
• 1887 – Floris Osmond gives the name and symbols associated to the phases of steel.
• 1896 – First attempt at the Fe-C diagram of steel by Albert Sauveur.
• 1897 – Roberts-Austen provides the complete Fe-C diagram. He also described the high temperature phase of steel (austenite).
• 1900 – Hendrik Willem Bakhuis Roozeboom publishes the Fe Fe₃C diagram taking into accounts Gibbs phase rule.
• 1906 – Alfred Wilm discovers age hardening by accident.
• 1919 –Gustav Heinrich Tammann predicts the order-disorder transition of alloys at low temperature
• 1922 – Arne Westgren [de] and Robert P. Fragman showed that the γ phase of steel is face-centered cubic (fcc), while the α, β and δ phases are body centered cubic.
• 1923 – Edgar Bain discovers superlattices
• 1926 – Bain describes the atomistic formation of martensite.
• 1930 – Georgy Kurdyumov and George Sachs reveal the orientation of martensite and austenite, now named the Kurdyumov–Sachs orientation.
• 1947 – Ernest Kirkendall experiment reveals the vacancy mechanism of diffusion. It's discovery was called the Kirkendall effect.
• 1953 – E. O. Hall and independently N. J. Petch publish their theory of grain boundary strengthening (Hall–Petch law).

See also

• Extractive metallurgy