Text C: «METALWORKING AND METAL PROPETIES» An importantfeature of hot working is that itpro­vides theimprovement of mechanicalproperties of met­als . Hot-working (hot-rolling or hot-forging)eliminates porosity, directionality, andsegregation that are usu­ally present in metals. Hot-worked products have better ductility and toughness than the unworkedcasting. Dur­ing the forging of a bar, the grains of the metal become greatlyelongated in the direction of flow. As a result, the toughness of the metal is greatly improved in this direction andweakened in directionstransverse to the flow. Good forging makes the flow lines in thefinishedpart oriented so as to lie in the direction of maximum stress when the part is placed in service.

The ability of a metal to resist thinning and fracture during cold-working operations plays an important role in alloy selection. In operations that involve stretching, the best alloys are those which grow stronger with strain (are strain hardening) - for example, the copper-zinc alloy, brass, used for cartridges and the aluminum-mag­nesium alloys in beverage cans, which exhibit greater strain hardening.

Fracture of the workpiece during forming can result frominner flaws in the metal. These flaws often con­sist of nonmetallicinclusions such as oxides or sulfides that aretrapped in the metal duringrefining. Such in­clusions can beavoided by proper manufacturing pro­cedures.

The ability of different metals toundergo strain var­ies. The change of the shape after one forming operation is often limited by thetensile ductility of the metal. Met­als such as copper and aluminum are more ductile in such operations than other metals.

General understanding:

1. What process improves the mechanical properties of metals?

2. What new properties have hot-worked products?

3. How does the forging of a bar affect the grains of the metal? What is the result of this?

4. How are the flow lines in the forged metal oriented and how does it affect the strength of the forged part?

5. What are the best strain-hardening alloys? Where can we use them?

6. What are the inner flaws in the metal?

7. Can a metal fracture because of the inner flaw?

8. What limits the change of the shape during forming operations?

Exercise 2.5. Find the following in the text:

1. важная особенность горячей обработки

2. улучшение механических свойств металла

3. необработанная отливка

4. направление максимального напряжения

сопротивляться утончению и разру­шению

6. проявлять большее деформационное упрочнение

7. разрушение детали при штамповке

8. внутренние дефекты в металле

9. неметаллические включения

металлов подвергаться деформации

11. ограничивается пластичностью металла при ра­стяжении

Exercise 2.6. Translate into English:

1. Горячая обработка металла улучшает его меха­нические свойства и устраняет пористость и внутрен­ние дефекты.

2. Удлинение зерен в направлении текучести при ковке значительно улучшает прочность металла в этом направлении и уменьшает его прочность в поперечном.

3. Хорошая проковка ориентирует линии текучес­ти в направлении максимального напряжения.

4. Деформационное упрочнение металла при холод­ной обработке очень важно для получения металлов с улучшенными свойствами.

​

Lord Nelson (29 September 1758 – 21 October 1805) English naval commander who died during the Battle of Trafalgar, leading Britain to victory over the French navy – a key moment in the Napoleonic Wars.

‘England expects that every man will do his duty’ – Lord Nelson shortly before the Battle of Trafalgar, 1805  lord nelsonLord Nelson was one of Britain’s greatest naval commanders. He had a long and distinguished career, in which he gained a reputation as a master tactician and for his great personal bravery. His crowning moment came at the Battle of Trafalgar, where Britain’s decisive victory over Napoleon’s fleet ended the threat of a French invasion. He was born in 1758 in Burnham Thorpe, Norfolk, the sixth of eleven children. At the age of only 12, he joined the navy as an apprentice working in the lowest naval ranks. However, his aptitude and enthusiasm for the job saw him rapidly rise through the ranks, until he was given his own ship and made a captain at only 20 years old. This rapid advancement through the ranks occurred despite suffering an acute form of sea-sickness which dogged him throughout his life. His first service was in the West Indies, where he was involved in managing Britain’s commercial interests. However, after the US revolutionary wars ended, there were cutbacks to the navy and Horatio found himself out of work and surviving on half pay. He returned to England with his wife, Frances Nesbet.

However, the French revolutionary wars saw Nelson re-employed and he became engaged in battles around the Mediterranean. He achieved notable victories against the Spanish at Cape Vincent (1797) and the Battle of Copenhagen (1801). Nelson developed a reputation as a very good commander, who was daring, bold and – when necessary – willing to disobey orders. He also picked up several serious injuries and was blinded in one eye. When he was given a command to withdraw at the Battle of Copenhagen, he ignored the command putting his telescope to his blind eye and pretending not to see. His boldness paid off – with his persistence gaining victory. Nelson was a complex character; at a time when navy discipline was often extremely severe, he was said to have had empathy and love for his men – he didn’t adopt an overly authoritarian manner. His men definitely responded to his courage and confidence. But, he was also vain and loved to be flattered and receive praise. He had a great need for attention and was often bedevilled by insecurities. However, he was admired as a leader with a very strong sense of duty to his country. in 1787, Nelson married Frances Nisbet on her native island of Nevis in the Caribbean. However, several years later in Naples, he met and fell in love with Lady Emma Hamilton and became increasingly estranged from his wife. Despite both their marriages, Nelson and Emma continued a long public love affair, and had one child out of wedlock. Nelson considered Emma to be his true soul-mate. By 1801, Nelson’s prowess had led him to be appointed a vice-admiral and he became increasingly engaged in the Napoleonic wars with France. In 1805, Napoleon’s reach extended across France, and Britain was under real threat of invasion. However, under Nelson’s command, France was defeated and the threat of invasion receded. Tragically, the victory cost Nelson his life – dying in battle. After being shot he said: “Hardy, I do believe they have done it at last… my backbone is shot through.” After been taken below deck, he knew he would die. Shortly before his death, he was heard to murmur – ‘Thank God I have done my duty’. This death in victory made Nelson a huge symbol of national pride and he was given a full state funeral. Nelson’s column was later erected in his honour. On hearing of Nelson’s death, despite a famous victory, King George III is said to have burst into tears saying. “We do not know whether we should mourn or rejoice. The country has gained the most splendid and decisive Victory that has ever graced the naval annals of England; but it has been dearly purchased.”

как то так

Hi! My name is Oleg. I live in Moscow. Last August we went to Adler — a small town near Sochi. It is situated in the South of our country. Adler is not so famous as Sochi but it has a very good airport and it is certainly one of the favourite places in Russia to spend holidays. The town of Adler is situated at the Black Sea. It has green streets and comfortable hotels. Its people are nice and friendly. We stayed at a small hotel near the sea and went swimming and boating every day. We played volleyball and had fun too. We always had dinner at a small café near the hotel. The food there was always fresh and tasty. In the evening we went to the cinema or watched video films. We had a very good time in Adler. I’d like to go there again.