Answer the following questions:



1. What are the raw materials for the production of copper?

2. Why must all copper ores be concentrated by flotation?

3. Whаt purpose is pure copper chiefly used for?

4. What properties does the alloying of copper with other elements increase?

5. What main groups do copper alloys comprise?

6. What alloys of copper are called bronzes?

 

7. Into what groups are bronzes divided?

8. Why are aluminium bronzes frequently used in foundry practice?

TITANIUM AND ITS ALLOYS

As an engineering material titanium has been widely applied only in the last years.

Titanium is a silvery-white metal which melts at approximately 1668°C and has a specific gravity of 4.505. Commercially pure titanium possesses high strength prop­erties. The tensile strength of most titanium alloys ranges from 100 to 140 kg/mm2, in conjunction with high elongation.

The hardness, tensile strength and yield point of tita­nium are increased with the degree of cold deformation. The elongation value drops rapidly when the degree of cold deformation (reduction) exceeds 50 per cent and becomes equal to 10 per cent. Impurities found in com­mercial titanium can be divided into two groups: elements which form interstitial solid solutions with titanium (O2, N, C and H2) and elements which form substitution solid solutions (Fe and other metallic elements). The first have a much greater effect on the mechanical properties than those in the second group.

Even very small amounts of oxygen and nitrogen in titanium alloys sharply reduce the ductility. A carbon content of more than 0.2 per cent reduces both the ductility and impact strength of a titanium alloy. It is supposed that the brittleness of titanium is a result of strain ageing and is connected with the presence of dissolved hydrogen in the beta-phase.

Titanium and its alloys are hardened either by a sur­face heat treatment followed by ageing at 400°—500° C or by producing a case which contains nitrogen, carbon and boron Industrial titanium alloys contain vanadium, molybdenum, chromium, manganese, aluminium, tin, iron or other elements, singly or in various combinations.

A combination of high mechanical properties with low specific weight and excellent corrosion resistance enables titanium to be used in building supersonic air craft.

Answer the following questions:

1. What is titanium?

2. What does the hardness, tensile strength and yield point of titanium depend upon?

3. Do very small amounts of oxygen and nitrogen in titanium alloys reduce the ductility?

4. How are titanium and its alloys hardened?

5. What constituents do industrial titanium alloys contain?

 

 

GRAMMAR TEST

1. What is this? … is my dictionary.
a. it
b. these
c. those
d. they
e. them

2. There is … pencil on the table.
a. some
b. such
c. an
d. a
e. three

3. … car is this?
a. what
b. who’s
c. why
d. whom
e. whose

4. I’m cold. …open the window.
a. a not
b. don’t
c. no
d. none
e. –

5. He … to the University by bus.
a. is going
b. can
c. goes
d. go
e. are going

6. Paul … a book now.
a. is reading
b. are reading
c. read will read
d. had read

7. I like bananas, but I … them every day.
a. haven’t eat
b. not eat
c. doesn’t eat
d. don’t eat
e. isn’t eating

8. I … to see my friend tomorrow.
a. are going
b. have going
c. is going
d. were going
e. am going

9. She didn’t … breakfast yesterday.
a. had
b. has
c. have
d. having
e. haved

10. I can swim, but my friend …
a. is not
b. can’t
c. don’t
d. needn’t
e. aren’t

11. … I take your pen?
a. may
b. will be able
c. does
d. has
e. had

12. Must I wear these shoes? – No, you…
a. mustn’t
b. can’t
c. weren’t
d. isn’t
e. aren’t

13. My grandfather … to leave school when he was 15.
a. must
b. can
c. is
d. are
e. had to

14. I … speak French last year.
a. can’t
b. may not
c. must not
d. couldn’t
e. hasn’t

15. You will … speak English in 3 years.
a. can
b. has
c. had
d. be able to
e. were able to

16. When I called him, he … supper.
a. has having
b. was have
c. was having
d. is having
e. were having

17. They … up late yesterday.
a. get
b. got
c. has got
d. gets
e. getting

18. It is the … book I have ever read.
a. best
b. better
c. well
d. good
e. worse

19. Where … go? Let’s go to the cinema.
a. won’t we
b. is we
c. have we
d. shall we
e. are we

20. What has she … ?
a. doing
b. do
c. did
d. done
e. does

21. There … many students in the room now.
a. were
b. was
c. is
d. are
e. will

22. There … a university in the centre of the city.
a. is
b. are
c. be
d. shall
e. were

23. I can’t see … on my table.
a. nothing
b. nobody
c. anything
d. anywhere
e. somewhere

24. What … you going to do tonight?
a. was
b. will
c. were
d. is
e. are

25. There … any sugar in the tea.
a. weren’t
b. wasn’t
c. haven’t
d. hadn’t
e. won’t

26. We … in Moscow last year.
a. lives
b. is living
c. has living
d. live
e. lived


27. Where … she work?
a. do
b. done
c. doing
d. does
e. is

28. ... speaks English well?
a. which
b. why
c. who
d. when
e. what

29. How many theatres … there in your city now?
a. were
b. are
c. have
d. is
e. was

30. What … you do tomorrow?
a. will
b. shall
c. will be
d. shall be
e. are

31. He said that he … at the plant last year.
a. are having
b. living
c. lives
d. had lived
e. lived

32. Let … tell his friends about his city.
a. his
b. him
c. he
d. her
e. she

33. My friend … breakfast when I called him.
a. were having
b. will having
c. are having
d. was having
e. is having

34. What … do you want to read?
a. another
b. yet
c. other
d. still
e. else

35. Which is the … river in our country?
a. long
b. longer
c. longest
d. large
e. larger

36. There was … in the room.
a. somebody
b. somewhere
c. anybody
d. anything
e. some

37. Who … you this story yesterday?
a. speak
b. tell
c. told
d. spoke
e. said

38. When we came in, the film … already begun.

a. are
b. is
c. were
d. was
e. had

39. The work … done well two days ago.
a. has done
b. was done
c. has been done
d. was do
e. did

40. Books by Dickens … many times.
a. is publishing
b. have published
c. are published
d. were published
e. is published

41. What … you do every day?
a. does
b. do
c. did
d. doing
e. done

42. This problem … tomorrow.
a. will be discussed
b. have been discussed
c. is discussing
d. will discuss
e. had discussed

43. I wonder, why there are so … people.
a. no
b. such
c. some
d. much
e. many

44. I am sorry… I come in?
a. could
b. might
c. may
d. must
e. need

45. I … do this work yesterday. I was busy.
a. mustn’t
b. can’t
c. couldn’t
d. aren’t
e. weren’t

46. What … you doing here?
a. are
b. is
c. will
d. be
e. can

47. He … going to translate this article.
a. do
b. have
c. may
d. is
e. are

48. These pictures … by a young painter last year.
a. are painted
b. were painted
c. is painted
d. will be painted
e. have been painted

49. I … know him.
a. doesn’t
b. haven’t
c. hasn’t
d. isn’t
e. don’t

50. … go to the library.
a. won’t
b. doesn’t
c. don’t
d. haven’t
e. isn’t

51. Do you often … English to your teacher?
a. spoken
b. spoke
c. speak
d. speaking
e. speaked
52. … of you likes to speak French?
a. which
b. who
c. why
d. what
e. whom


53. … of you lives in the centre of Moscow?
a. whom
b. whose
c. who
d. which
e. when

54. How long does your working day …?
a. has lasted
b. is lasting
c. lasted
d. last
e. lasting
55. My sister works ...
a. many
b. much
c. some
d. not many
e. none

56. What … they discussing now?
a. are
b. were
c. will
d. is
e. was

57. Will you … at home tomorrow?
a. is
b. were
c. are
d. be
e. have

58. They … here an hour ago.
a. have
b. have been
c. was
d. were
e. are

59. I wrote him a letter …
a. since
b. today
c. last month
d. this month
e. tomorrow

60. … children don’t like to play football.
a. some
b. no
c. any
d. anybody
e. somebody

61. There … many children in the park yesterday.
a. hadn’t
b. aren’t
c. haven’t
d. wasn’t
e. weren’t

62. Where … we get these journals?
a. do
b. can
c. must
d. were
e. will

63. … I ask you a question? – Certainly.
a. am
b. must
c. may
d. was
e. will

64. He … come yet.
a. haven’t
b. didn’t
c. hasn’t
d. doesn’t
e. can’t

65. I was waiting … you at 5 o’clock yesterday.
a. with
b. at
c. for
d. in
e. –


66. Have you … the translation yet?
a. does
b. doing
c. do
d. did
e. done

67. Is … a library at your office?
a. where
b. there
c. anywhere
d. somewhere
e. nowhere

68. These books are too difficult .. me.
a. about
b. at
c. of
d. for
e. with

69. …you know about it yesterday?
a. hasn’t
b. haven’t
c. don’t
d. didn’t
e. doesn’t

70. You can help me, … you?
a. can’t
b. can
c. couldn’t
d. won’t
e. don’t

71. You didn’t see him last week, … you?
a. didn’t
b. did
c. does
d. doesn’t
e. won’t

72. … usually takes me half an hour to get to my office.
a. he
b. I
c. what
d. it
e. she

73. I’m hurrying … the University.
a. to
b. of
c. at
d. in
e. –

74. What is he afraid … ?
a. to
b. in
c. with
d. of
e. off

75. There … a lot of students at the lecture tomorrow.
a. will
b. will be
c. will have
d. will can
e. were

76. He won’t go to the cinema tomorrow, … he?
a. will
b. won’t
c. won’t be
d. didn’t
e. did

77. Here is the man … wanted to speak to you.
a. which of
b. which
c. who
d. whom
e. whose

78. He will come back … Simferopol in June.
a. –
b. of
c. at
d. in
e. to


79. I didn’t do my work …. I was busy.
a. that’s why
b. because
c. in order to
d. after
e. before

80. … you swim last year?
a. could
b. can
c. was able
d. will be able
e. could able

81. I … seen him this week.
a. hasn’t
b. haven’t
c. didn’t
d. don’t
e. doesn’t

82. You were waiting for me at 2 o’clock yesterday, … you?
a. aren’t
b. didn’t
c. wasn’t
d. weren’t
e. haven’t

83. Mr. Green won’t be able to come, .. he?
a. shall
b. will
c. can
d. has
e. does

84. He … a cup of coffee when the telephone rang.
a. drink
b. are drinking
c. is drinking
d. drank
e. was drinking

85. The company has so … money.
a. little
b. less
c. more
d. many
e. the least

86. I … going to invite you to my birthday party.
a. has
b. have
c. are
d. is
e. am

87. You … English before entering the University
a. has study
b. has studied
c. had studied
d. had study
e. studied

88. New York is the … city in the USA.
a. most large
b. larger
c. large
d. largest
e. much largest

89. Who is your … friend?
a. goodest
b. best
c. better
d. more better
e. most

90. He … always waited for.
a. being
b. been
c. has
d. are
e. is

91. Who … asked when you came in?
a. was
b. been
c. was being
d. were
e. were being


92. Many new houses … built in our city lately.
a. has been
b. had been
c. have been
d. have being
e. being

93. I … wait for him now. I am very busy.
a. can’t
b. couldn’t
c. wasn’t
d. hadn’t
e. hasn’t

94. He … many friends here.
a. have
b. haves
c. has
d. having
e. had had

95. Will you … to come tomorrow?
a. will able
b. had able
c. was able
d. able
e. be able

96. You must … to answer all my questions.
a. was ready
b. be ready
c. is ready
d. are ready
e. ready
97. … you learn English?
a. haven’t
b. aren’t
c. isn’t
d. don’t
e. doesn’t

98. How many lessons … you have every day?
a. do
b. does
c. have
d. has
e. are
99. You like watching TV- programmes, … you?
a. do
b. don’t
c. doesn’t
d. does
e. did

100. What … your favourite subject at school?
a. did
b. has
c. are
d. were
e. was

 

 

Литература

  1. Алехина М.С. Английский для металлургов. М.: Русский язык, 2005.
  2. Андреев Г.Я., Гураль Л.Л., Лев А.Л. Сборник технических текстов на английском языке. М.: Издательство «Высшая школа», 1972.
  3. Иллюстрированный словарь английского и русского языка с указателями. М.: Живой язык, 2003.
  4. Парахина А.В. Пособие по переводу технических текстов с английского языка на русский. М.: Издательство «Высшая школа», 1972.
  5.  А.И. Каменский, И.Б. Каменская. Практическая грамматика английского языка. 2002.

 


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