28 May 2024 : The Hindu Editorial

Editorial 1 : At extremely high strain rate, copper surprises with the strength of steel

Introduction

The discovery of steel transformed the course of human civilisation. The stone age ended with the invention and widespread use of copper smelting and alloying copper with other elements, thus introducing metalworking, new and more durable agricultural implements, the development of culture, trade, and governments, and new weapons of war.

The metals

• When heated, copper turns to liquid, after which it can be moulded into a desired shape. When the mould is cooled, the metal returns to its original solid state, this time in the mould’s shape.
• Iron replaced copper and tin in the iron age, but it also did something neither metal could: dissolve carbon.
• If iron is heated and cooled repeatedly, such that the dissolved carbon is removed until a small amount remains, the powerful iron-carbon alloy known as steel is born. Unlike copper or tin, or even iron, steel is hard — and this made all the difference.
• If only the people of the bronze age had kept heating copper while straining it greatly, they’d have come across a form of the metal that could rival steel.

Deformation and strain rate

• A study reported that when pure copper is heated and also subjected to an extreme strain rate, it behaves like a much harder material would.
• They attribute this counterintuitive behaviour to new “strengthening mechanisms” that are activated in the material by the higher strain rate.
• The findings could give rise to new strategies for designing devices to use in extreme conditions like high-speed manufacturing or aerospace engineering, where high temperatures and strain rates are common.
• Scientists have already subjected many materials to high strain rates and studied their properties in detail.
• In the new study, the researchers breached new ground by imparting an even greater strain rate using cutting-edge material-testing technologies.
• Strain is how much a material deforms when stress is applied. A steel ingot is stronger and will require a lot more stress to achieve the same amount of strain. Those of copper or iron will require less.
• Strain rate measures the rate at which strain changes. Its unit is (metres per second) per metre, effectively per second.

Sources of strength

• In their study, the researchers accelerated aluminium oxide microparticles using lasers and shot them at a copper substrate at around 860 km/hr.
• They found that as the temperature is increased, the impact crater depth and width decrease meaning the copper was behaving at the impact spot like a harder material. Note that the hardness is restricted to the neighbourhood of the impact even if the whole material is maintained at that temperature.
• The copper in the researchers’ test had three sources of strength: drag-strengthening, thermal, and athermal.
• The purpose of each source is to prevent a particular dislocation from propagating through the material.
• Drag-strengthening refers to interactions between parts of the material dislocated by a stress and vibrational energy in the atomic lattice.
• Thermal strength refers to the kinetic energy of the atoms in the lattice and their ability to suppress the effects of certain defects in the material.
• Athermal strength refers to barriers to dislocation other than the atoms’ kinetic energy, such as the interface between two crystal structures.

Conclusion

• Since the bronze age, metals have penetrated almost all walks of life — from cookware to spaceflight, from office stationery to weapons of mass destruction. In many of these applications, they need to withstand sudden, intense impacts.
• The new study throws a spanner in this thinking by revealing a change in the material’s strength response above a strain rate of around 1 million/s.
• Even at room temperature (20 degrees C), for example, the study found that the copper substrate had four-times more dynamic strength under a strain rate of 1 million/s than without any strain.

Editorial 2 : India relies on China for most electronic and electrical goods

Context

India sources over 50% of its mobiles, automatic data processing units, and semiconductor devices from China.

Again, Made in China!

• In FY24, China once again became India’s top trading partner.
• This is the sixth time in the last 10 years that China has beaten the U.S. to emerge as India’s top partner.
• A country is designated as a top trading partner if the total value of India’s exports to it and imports from it exceeds that of any other country.
• Notably, China’s status as India’s top trading partner is primarily due to the exceptionally high volume of imports from China, which overshadows the relatively low volume of exports to China by India.
• That is why India’s trade deficit with China has been widening the fastest, in absolute terms, compared with other partners.

• India’s trade relationship with the U.S. is the opposite, with India exporting more to the U.S. than what it imports. In fact, the gap between imports and exports, or the trade balance (trade surplus in this case), has been widening in recent years.

Detailed analysis

• While imports from China have surged, exports to China have remained stagnant. On the other hand, exports to the U.S. as well as imports from the U.S. have increased, though the degree of increase in exports was greater than that of the imports.
• Among India’s partners, China and the U.S. occupy the two extreme ends. With the U.S., India has a trade surplus of $36.7 billion, while with China, India has a trade deficit of $85.1 billion in FY24. Both these figures are the highest ever trade surplus and trade deficit recorded with the respective countries.
• The trade deficit with Russia has skyrocketed in recent years, from just $6.6 billion in FY22 to $57.2 in FY24. A majority of this is due to the import of oil at a discounted price from Russia, after the West imposed sanctions on the country. Russia is currently the chief oil source for India.
• India’s trade surplus with the Netherlands has increased; this is also connected to the sanctions on Russia.
• About 40-45% of the crude oil sourced from Russia is converted to petrol, diesel, and other products by Indian refineries and sold to the Netherlands. The European country is sourcing petroleum products from India and not directly from Russia due to the sanctions. It then redistributes these products among its neighbours.

Items imported from China

• A majority of the items that India imports from China can be classified as electronics and electrical items.
•  In the FY15 to FY24 period, India imported $75 billion worth of mobiles/telephones, the biggest component in the import basket.
• This was followed by automatic data processing units, semiconductor devices and diodes and electronic integrated circuits .
• Not only is India buying electrical and electronic items from China in bulk, but also, China is the major source for most of these items, with very few alternatives.
•  India sourced 54% of its mobiles/telephones from China in the FY15 to FY24 period. It also sourced close to 56% of automatic data processing units, about 70% of semiconductor devices and diodes, and 32% of electronic integrated circuits and micro assemblies from China in this period.

Way forward

Reducing import dependency from China involves diversifying supply chains, incentivizing domestic production, investing in research and development for key industries, fostering partnerships with other countries for trade, and implementing policies that support local manufacturing.