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EXAM SECTION I: 25 points MATERIALS: Units MARCH 12:00 room 041

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1 EXAM SECTION I: 25 points MATERIALS: Units 1-5 29 MARCH 12:00 room 041
Multiple choice (penalty = 3 wrong answers = -1) Fill-in the gaps Correct the mistakes Reading comprehension VIDEO test: during Practical Session 4 (U6) Sample & solution and BOOK solutions: personales.upv.es/ajaime

2 UNIT 5 CAUSE & EFFECT Vocabulary Grammar and functions
Heat treatment of steel: annealing hardening Tempering WORD FORMATION (U2->p28): N from Vbs Grammar and functions Expressing cause & effect =CONNECTORS ALLOW / CAUSE / AVOID

3 CAUSE & EFFECT CAUSE BECAUSE
SINCE + SENTENCE (S+Vb) porque, puesto que, ya que AS Debido a + NOUN / Vb -ING DUE TO BECAUSE OF + NOUN / VB -ING OWING TO Debido a QUE + SENTENCE (S+Vb) DUE TO THE FACT THAT + (Sentence) BECAUSE OF THE FACT THAT + (Sentence) OWING TO THE FACT THAT + (Sentence) ONE EFFECT / RESULT / CONSEQUENCE OF C IS E

4 C RESULTS IN E dar como resultado C BRINGS ABOUT E provocar,
CAUSE & EFFECT VERBS C RESULTS IN E dar como resultado C BRINGS ABOUT E provocar, C GIVES RISE TO E implicar, suponer C LEADS TO E lleva/conduce a C CAUSES/ALLOWS E hace que (+Vb) BECOMES (+ adj) resulta + ADJ

5 C, SO THAT E de modo que / para que
CAUSE & EFFECT EFFECT THEREFORE, por lo tanto THUS, así, HENCE, así pues CONSEQUENTLY, AS A CONSEQUENCE, AS A RESULT, DUE TO THIS, como consecuencia, THEREBY de este modo IN THIS WAY … C, SO THAT E de modo que / para que

6 EXERCISE We use copper in wires due to its ductility
We mix pure metals with other materials so that we obtain the required properties Aluminium is used in structures as it is corrosion resistant Aluminium is used in structures because of its corrosion resistance Tempering results in a decrease in hardness and ... Plastics are insulators, thus they are used to cover wires Annealed steel is more machineable since this process releases internal stresses With hardening, the metal becomes stronger Iron is brittle. As a consequence it is mixed with other ... Alloying is a way of changing the properties of metals. In this way we can obtain materials with specific characteristics

7 QUESTIONS Which two methods are used to change the properties of steel? How does the carbon content affect the properties of steel? What does heat treatment consist of? What happens when we heat steel at a certain temperature? Which are the three heat treatments? What two steps are involved in the process of annealing? Which are the results? What happens when we cool the metal quickly? What two steps are involved in the process of hardening? What problem results from hardening and how can we solve this? Explain the process of tempering. What is the difference between tempered steel and high carbon steel?

8 TRUE/FALSE Carbon makes steel harder. T (up to 1.5%)
When we want to make steel softer and easier to machine we use annealing. T Annealing increases the internal stresses in the metal. F (Annealing releases stresses) Steel can be hardened by cooling it slowly. F (by cooling it fast) High carbon steel can be easily worked because it is soft. F (it becomes hard)

9 WORD FORMATION (U2 p 28) NOUN from VERB
-ing -> English (e.g. building) -tion/sion ->Latin (e.g. Explanation/emission) -ment (e.g. management) er/or (object) (e.g. boiler/conductor) ure (e.g. mixture) ent/ant (e.g. content/coolant) nce (e.g. performance) age (e.g. drainage) al (e.g. disposal) y (e.g. discovery) WORD FORMATION (U2 p 28)

10 WORD FORMATION: p 28 EXPOSURE to GASEOUS fluorine.
IMPROVEMENTS … RESISTANCE …FULLY … PITTING DENSITY … its SUBSTITUTION …. WEIGHT …HARMFUL … EMISSIONS its STRENGTH … its ABILITY … DEFORMATION …its RESISTANCE … to DEFLECTION COMPONENTS … CHEMICALLY …. ENVIRONMENTALLY safer COOLANTS … higher PRESSURES

11 WORD FORMATION: Aluminium p 29
ACTIVITY ENGINEERING DEVELOPMENT APPLICATIONS TOUGHNESS or DUCTILITY FAILURE. ACCEPTANCE COMPONENTS REFRIGERANTS or COOLANTS and PRESSURES WORKABILITY and corrosion RESISTANCE ABILITY STRENGTH TREATMENT

12 WORD FORMATION PercentAGE hammerING contractION crackING temperING
annealING CoolING DistortION treatMENT hardENING

13 CAUSE/PERMIT/PREVENT (U5 p60)
CAUSE: TO CAUSE + OBJ + TO INFINITIVE TO MAKE + OBJ + BASE FORM OF THE VERB hacer que + frase PERMIT: TO ALLOW + OBJECT + TO INFINITIVE TO PERMIT + OBJECT + TO INFINITIVE TO ENABLE + OBJECT + TO INFINITIVE TO LET + OBJECT + BASE FORM OF THE VERB permitir que + frase PREVENT: TO PREVENT + OBJECT + FROM + -ING TO AVOID + OBJECT + FROM + -ING TO STOP + OBJECT + FROM + -ING TO KEEP + OBJECT + FROM + -ING impedir que + frase

14 EXERCISE CAUSE/ALLOW/PREVENT (p60)
The recommendation of various alternatives can permit the company to determine which one is best for the particular situation. Chemical degradation is a process in which additives cause plastics to crumble away. The composite fibers prevent some kinds of brittle materials from cracking. Known as rapid solidification, the process causes the atoms to freeze in place before they can align in a crystalline lattice. Lighter and more heat tolerant than metals, ceramics permit the engine to run hotter, and therefore more efficiently. When ceramic is unable to bend, a strong impact will cause it to crack. Stress ceramics prevent the crystalline planes from deforming. Superconductors permit electrons to flow indefinitely. Carbon dioxide permits the infrared rays to pass through the atmosphere but prevents them from leaving again. Insulators prevent electrons from flowing through them.

15 LISTENING (p61): STEEL an alloy of IRON and up to 1.7% CARBON, with small amounts of manganese, phosphorous, sulfur, and silicon those with other metals low-alloy steels have LESS THAN 5% of the alloying metal and high-alloy steels MORE THAN 5%. Carbon steels are FAR STRONGER THAN IRON, and their properties can be tailored to their uses by adjusting COMPOSITION AND TREATMENT. STAINLESS STEELS Steel was first mass-produced in the MID-19TH CENTURY The USA, the former Soviet Union, and Japan are the MAJOR PRODUCERS. All steelmaking processes REMOVE THE IMPURITIES in the raw materials …and reduce iron ore BY OXIDIZING them WITH an air or oxygen blast

16 LISTENING: STEEL THUS MOST OF THE CARBON, SILICON, manganese, phosphorus and sulfur ARE CONVERTED TO THEIR OXIDES and, … The main processes are …and the open-hearth process 10. When the impurities have been removed, DESIRED ELEMENTS ARE ADDED IN CALCULATED PROPORTIONS 11. steel is cast as INGOTS that are shaped while still red-hot in rolling mills, or it may be cast as a continuous bar (strand casting). 12. The properties of carbon steels may be greatly improved by HEAT TREATMENT: ANNEALING, CASE HARDENING and TEMPERING

17 HEAT TREATMENT 1 THE PROPERTIES OF METALS CAN BE CHANGED IN DIFFERENT WAYS. A COMMON METHOD OF IMPROVING THEIR CHARACTERISTICS IS BY ALLOYING SEVERAL METALS. THIS METHOD CONSISTS OF HEATING THE METALS UNTIL THEY MELT IN ORDER TO OBTAIN THE REQUIRED PROPERTIES. FOR EXAMPLE, STEEL CONTAINING LITTLE CARBON WILL be SOFTER than steel with more carbon

18 HEAT TREATMENT 2 ON THE OTHER HAND, THE PROPERTIES OF STEEL CAN ALSO BE IMPROVED BY HEAT TREATMENT. THIS IS THE NAME GIVEN TO A NUMBER OF PROCEDURES WHICH CONSIST OF HEATING THE METAL UP TO A CERTAIN TEMPERATURE AND THEN ALLOW THE METAL TO COOL AT DIFFERENT RATES

19 HEAT TREATMENT 3 ONE OF SUCH PROCEDURES IS KNOWN AS ANNEALING. IN THIS PROCESS, STEEL IS HEATED ABOVE ITS CRITICAL TEMPERATURE AND THEN IT IS COOLED SLOWLY. 4 AS A RESULT, THE METAL BECOMES SOFTER AND MORE EASILY MACHINABLE DUE TO THE FACT THAT THIS PROCESS PREVENTS INTERNAL STRESSES FROM OCCURRING

20 HEAT TREATMENT 5 AS OPPOSED TO ANNEALING, WE CAN MAKE THE METAL HARDER WITH THE PROCESS OF HARDENING. IN THIS CASE, WE LET THE METAL HEAT ABOVE ITS CRITICAL TEMPERATURE AND THEN WE ALLOW IT TO COOL FAST. 6 ON THE CONTRARY TO WHAT HAPPENED IN THE PROCESS OF ANNEALING, THE METAL OBTAINED WILL BE HARDER; HOWEVER, IT WILL BE BRITTLE SINCE THE RAPID COOLING CAUSES UNEQUAL CONTRACTIONS TO OCCUR IN THE METAL, WHICH GIVES RISE TO CRACKING

21 HEAT TREATMENT 7 IN ORDER TO AVOID THIS PROBLEM, THE METAL CAN BE HEATED BELOW ITS CRITICAL TEMPERATURE AND INSTEAD OF COOLING IT QUICKLY WE LET IT COOL SLOW LY; IN THIS WAY, DESPITE THE METAL BEING HARD, IT WILL ALSO BE TOUGH THUS ALLOWING US TO SHAPE IT WITHOUT FRACTURING


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