The use of metals by humans, the past, present, and future of metallic materials
I. The Development History of Metallic Materials
Phase 1 – Use of Native Metals, Emergence of Iron and Steel
(1) Around 5000 BCE: Use of native gold, copper, and lead; copper tools, gold artifacts, and combined use of copper and stone.
Between 5040–4840 BCE, the most notable tools from this period are 38 pieces of native copper unearthed in Plocnik, southern Serbia, dating to 5040–4840 BCE with a total weight of about 16 kg. The Balkan Peninsula was also the cradle of various early metallurgical techniques, including the smelting of lead, gold, tin bronze, and silver. For example, at the Belovode site (~5200 BCE), lead slag was discovered, possibly marking the birth of lead smelting. Meanwhile, gold smelting began in eastern Bulgaria around 4650 BCE, with the most remarkable finds being 3,100 gold artifacts (totaling 5 kg) from the Varna cemetery. Tin bronze smelting technology also developed in southern Serbia and across Bulgaria, with tin bronze fragments from Plocnik providing precise dating evidence. These discoveries collectively underscore the Balkans' pivotal role in early metallurgical advancements.
(2) Around 4000 BCE: Development of Copper Smelting
Around 6,000 years ago, copper smelting in eastern Turkey had already reached a high level of sophistication and gradually spread to neighboring regions. During this period, low-arsenic copper began appearing in many areas. By ~5500 BCE, people started intentionally producing copper alloys like arsenical copper.
(3) 4000–500 BCE: Emergence of Bronze to the Bronze Age
Southern Iran and Mesopotamia were using bronze tools by 4000–3000 BCE, as was Europe during the same period.
China’s earliest bronze artifacts date back to ~3000 BCE, while India and Egypt saw bronze use by 3000–2000 BCE. Africa adopted bronze later, no later than 1000 BCE–1 CE.
By ~2000 BCE, bronze tools became widespread, marking the Bronze Age. The term "Bronze Age" refers to the period from 2000–500 BCE, during which various bronze vessels, tools, and weapons emerged.
(4) Around 3000 BCE: Direct Use of Meteoric Iron from Nature
In ancient Egypt (~3500 BCE), iron artifacts containing 7.5% nickel were discovered, clearly indicating their extraterrestrial origin—specifically, meteorites. In 2013, a study published in Archaeometry analyzed iron beads from ~3200 BCE Egypt, confirming they were made from iron meteorites.
(5) 1500 BCE: Emergence of Iron Smelting Technology
The world's oldest smelted iron artifact is a copper-handled iron-bladed dagger from a Hittite tomb in northern Anatolia (Turkey), dating to 4500 years ago (2500 BCE). Radiocarbon dating confirmed its smelted origin, making it exceptionally valuable due to the 1000-year gap between this find and the subsequent widespread adoption of smelted iron.
China's oldest smelted iron artifacts are two iron bars from the Siwa culture tombs in Motan, Linxia County, Gansu Province, dating to 3510–3310 BCE (1510–1310 BCE).
By 1800 BCE, iron smelting technology had emerged in India.
Around 1500 BCE, the technique advanced, leading to widespread iron use in Egypt.
From ~1400 BCE, the Hittites and Assyrians near the Black Sea began large-scale production of iron tools and weapons.
(6) 1200 BCE: Advent of the Iron Age
By 1200 BCE, the gradual proliferation of iron tools marked the dawn of the Iron Age.
Middle East: Iron use began around 1200 BCE.
Eastern Europe: The Iron Age commenced circa 1000 BCE.
Central Europe: The period is divided into the Early Iron Age (800 BCE–450 CE) and Late Iron Age (from 450 BCE).
Britain and Ireland: Ironworking knowledge reached Britannia by ~500 BCE.
China: Widespread iron adoption occurred around 600 BCE.
(7)B.C1000Year: The emergence of steel
Metallurgists in the Iron Age have discovered that a by-product would occur accidentally during their iron smelting process - steel.
One of the earliest sources of the word "steel" was BC 7 Herodotus, a Greek historian in the centuryHerodotus) depicted by Gracos of Chios (Glaucus) Inlaid in a bowl of text.
B.C.3Century: India smelted "Uz Steel", and this material is still famous for its quality.
China's steelmaking history can be traced back to BC2In the century, its steelmaking process was close to the "Bessemay acid converter steelmaking method"
When steel and its superior properties were discovered, the Iron Age craftsmen made tools and weapons, such as knives. A new process soon emerged, such as quenching, which immerses the processed steel parts in water or oil to quickly cool them, thereby increasing their hardness. In an archaeology in Cyprus, it was discovered as early as BC 1100 Years of craftsmen knew how to make quenched and hardened knives.
However, steelmaking was still a cumbersome and difficult process in ancient times, so few steel products were regarded as extremely precious.
(8) 15th Century: Steel's Global Proliferation
By the 15th century, steel was ubiquitous worldwide. Sword-making epitomized its virtues—blades required toughness, hardness, and sharpness. From Damascus and Toledo blades to Japanese katanas, steel reigned supreme in elite weaponry.
Phase II - Foundations of Metallic Materials Science
Establishing the disciplinary foundations: metallography, metal physics, phase transformations, and alloy steels.
1803: Dalton proposed the atomic theory, Avogadro proposed the molecular theory.
1830: Hessel identified 32 crystal classes, popularizing crystal indexing.
1891: Scientists in Russia, Germany, and Britain independently established the lattice structure theory.
1864: Sorby produced the first metallographic micrograph (9x magnification), a groundbreaking achievement.
1827: Karsten isolated Fe₃C from steel; Abel confirmed this in 1888.
1861: Russian scientist Chernov proposed the concept of critical transformation temperatures in steel.
Late 19th century: Martensite research became fashionable; Gibbs formulated the phase rule, Roberts-Austen discovered the solid solution properties of austenite, and Roozeboom established the Fe-Fe₃C equilibrium diagram.
Phase III - Major Advances in Microstructure Theory
Development of alloy phase diagrams, invention and application of X-rays, establishment of dislocation theory.
1912: Discovery of X-rays, confirmation that α(δ)-Fe has bcc structure and γ-Fe has fcc structure; solid solution rules.
1931: Discovery of alloying elements' effects on expanding and contracting the γ-phase field.
1934: Polish scientist Polanyi, Hungarian Orowan, and British Taylor independently proposed dislocation theory to explain steel's plastic deformation and the crystallography of martensitic transformation.
1938: Invention of the electron microscope.
1910: Invention of A-type stainless steel, 1912 invention of F-type stainless steel, etc.
1990: Invention of the Brinell hardness tester; Griffith proposed that stress concentration leads to microcrack formation.
Phase IV - In-depth Study of Microstructure Theory
Advanced research in microstructure theory: investigation of atomic diffusion and its mechanisms; determination of TTT curves for steel; formation of comprehensive theories on bainite and martensite transformation.
Development of dislocation theory:
Invention of electron microscopy enabled observation of:
• Second-phase precipitation in steel
• Dislocation glide
• Discovery of partial dislocations, stacking faults, dislocation walls, substructures, Cottrell atmospheres, etc.
Advancement of dislocation theory
Continuous invention of new scientific instruments:
Electron probe microanalyzer (EPMA)
Field ion microscope (FIM) and field emission microscope (FEM)
Scanning transmission electron microscope (STEM)
Scanning tunneling microscope (STM)
Atomic force microscope (AFM)
II. Modern Metallic Materials
Research and development of advanced structural materials remains an eternal theme.
Development of high-performance structural materials: Pursuing high strength, high-temperature resistance, corrosion resistance, and wear resistance, while reducing mechanical weight, enhancing performance, and extending service life. Widespread application of composite materials as structural materials, such as aluminum matrix composites. Development of various series of low-temperature austenitic steels for specific applications.
Upgrading traditional structural materials: Key approaches include finer and more uniform microstructure, purer materials, and process optimization. "Next-generation steel materials" achieve twice the strength of conventional steels. The 9/11 attacks in the US revealed poor high-temperature softening resistance of structural steels, driving development of high-strength fire-resistant and weather-resistant hot-rolled steels.
Development of other high-performance steels: New tool steels with excellent toughness and wear resistance have been created using advanced processes and methods. Economical alloying is a key direction for high-speed steel development, while various surface treatment technologies for tool materials are significant for new tool material innovation.
Advanced manufacturing processes: Including semi-solid metal processing technology, maturation and application of Al-Mg alloy technologies. Pushing the boundaries of existing steel technologies and steel strengthening/toughening remain primary research directions.
III. Sustainable Development and Trends of Metallic Materials
In 2004, the concept of "Material Industry in a Circular Society - Sustainable Development of Material Industry" was proposed.
Microbial Metallurgy:
Waste-free production method already industrialized in many countries.
In the US, 10% of total copper production comes from microbial metallurgy.
Japan cultivates ascidians to extract vanadium.
Seawater as a liquid mineral contains over 10 billion tons of alloy elements.
Currently extractable elements include magnesium and uranium:
• ~20% of global magnesium production comes from seawater
• The US meets 80% of its magnesium demand from seawater sources
Circular Material Industry:
Adapting to contemporary needs by integrating ecological awareness into product and process design
Improving material utilization efficiency
Reducing environmental burden throughout production and usage cycles
Developing an industrial ecosystem that forms a virtuous cycle of "Resources → Materials → Environment"
Key trends in alloy development:
Emphasis on low-alloying and universal alloys
Formation of green/ecological material systems for better recyclability
Focus on developing green materials closely related to daily life and environmentally friendly materials
IV. Titanium Alloy: Known as the "Metal of Space" and the "Steel of the Future"
Titanium alloy refers to a variety of metallic materials made by combining titanium with other metals. Developed as an important structural metal in the 1950s, titanium alloy boasts high strength, excellent corrosion resistance, and superior high-temperature performance. Between the 1950s and 1960s, the focus was on developing high-temperature titanium alloys for aero-engines and structural titanium alloys for aircraft airframes. Titanium alloy maintains high strength under both high and low temperatures, and its corrosion resistance is unparalleled. Although titanium is relatively abundant in the Earth's crust (0.6%), its complex extraction process and high cost have limited its widespread application. Titanium alloy is expected to be one of the metallic materials that will make significant contributions to humanity in the 21st century.
In the 1970s, a series of corrosion-resistant titanium alloys were developed. Since the 1980s, corrosion-resistant titanium alloys and high-strength titanium alloys have seen further advancements. Titanium alloy is primarily used to manufacture compressor components for aircraft engines, followed by structural parts for rockets, missiles, and high-speed aircraft.
Since the 1970s, titanium alloy has been extensively adopted in civil aircraft. For example, the Boeing 747 passenger plane uses over 3,640 kilograms of titanium. Aircraft with Mach numbers exceeding 2.5 utilize titanium mainly to replace steel, thereby reducing structural weight. A notable example is the U.S. SR-71 high-altitude, high-speed reconnaissance aircraft (with a flight Mach number of 3 and an operational altitude of 26,212 meters), where titanium accounts for 93% of the aircraft's structural weight, earning it the title of an "all-titanium" aircraft.
V. Non-Ferrous Metals and Non-Ferrous Alloys
The industry faces severe challenges in sustainable development, primarily due to serious resource destruction, extremely low utilization rates, and alarming waste. Deep processing technologies remain outdated, with a lack of high-end products; innovation achievements are limited, and the industrialization of high-tech outcomes is insufficient. The mainstream focus is on developing high-performance structural materials and advanced processing methods, such as aluminum-lithium alloys and rapidly solidified aluminum alloys. Functional materials based on non-ferrous metals also represent a key development direction.
Non-ferrous metals, in the narrow sense (also called non-ferrous metals), refer to all metals except iron (sometimes excluding manganese and chromium) and iron-based alloys. They can be categorized into heavy metals (e.g., copper, lead, zinc), light metals (e.g., aluminum, magnesium), precious metals (e.g., gold, silver, platinum), and rare metals (e.g., tungsten, molybdenum, germanium, lithium, lanthanum, uranium). In the broad sense, non-ferrous metals also include non-ferrous alloys, which are alloys composed of one non-ferrous metal as the matrix (typically >50%) with one or more other elements added.
Non-ferrous alloys generally exhibit higher strength and hardness than pure metals, greater electrical resistance, a smaller temperature coefficient of resistance, and superior comprehensive mechanical properties. Commonly used non-ferrous alloys include aluminum alloys, copper alloys, magnesium alloys, nickel alloys, tin alloys, tantalum alloys, titanium alloys, zinc alloys, molybdenum alloys, and zirconium alloys.
Non-ferrous metals are indispensable basic materials and critical strategic resources for national economies, daily life, defense industries, and scientific/technological development. Modernization of agriculture, industry, defense, and science/technology all rely on non-ferrous metals. For instance, components of cutting-edge weapons (e.g., aircraft, missiles, rockets, satellites, nuclear submarines) and advanced technologies (e.g., nuclear energy, television, telecommunications, radar, computers) are predominantly made from light metals and rare metals among non-ferrous metals. Additionally, the production of alloy steels would be impossible without non-ferrous metals like nickel, cobalt, tungsten, molybdenum, vanadium, and niobium. In certain applications (e.g., power industry), the consumption of non-ferrous metals is also substantial. Many countries worldwide, especially industrialized nations, are competing to develop their non-ferrous metal industries and expand strategic reserves of these materials.
More: https://www.sinosteel-pipe.com/en/blog-5626921601861015.html
