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كانزاسازى Kanza sazi metallurgy كانزاسازى ئەندازیاری کانزاسازی Metallurgy كانزاسازى KanzaSazi كانزاسازى علم المعادن

Nov 01, 2014

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Engineering

كانزاسازى
Kanza sazi
metallurgy
كانزاسازى
ئەندازیاری کانزاسازی
Metallurgy
كانزاسازى
KanzaSazi
كانزاسازى
علم المعادن

  • 1. 2 Republic of Iraq Kurdistan Regional Government Metallurgy
  • 2. 3 Types of Materials Question: answer by true or false and then rewrite the false statements in the correct form. 1. The branch of metallurgy that deals with the structure of metals and alloys and its effect on their physical and mechanical properties is termed as process metallurgy. Answer: false the branch of metallurgy that deals with the structure of metals and alloys and its effect on their physical and mechanical properties is termed as physical metallurgy. Page 1 the branch deals with structure alloys effect is termed Atoms 2. Materials are generally classified as metals and polymers. Answer: false Materials are generally classified as metals, ceramics and polymers. Page 1 3. Metallurgy is a science that deals with metals and polymers. Answer: false metallurgy is a science that deals with metals alone. Page 1 4. polymers are extremely strong
  • 3. 4 Answer: false polymers are weak and extremely flexible. Page 1 5. Thermoset plastics soften when heated and hardened when cooled. Answer: false Thermo plastics soften when heated and hardened when cooled. Page 2 6. Metals are generally good electrical and thermal conductors due to the covalent bonded atoms. Answer: false Metals are generally good electrical and thermal conductors due to the metallic bonded atoms. Page 2 7. Thermo plastics are those polymers that can only be heated once to set into permanent shape. Answer: false Thermoset plastics are those polymers that can only be heated once to set into permanent shape. Page2 8. Isotopes of an element are formed when the number of protons is not fixed for all atoms. Answer: false isotopes of an element are formed when the number of protons is not fixed for all atoms. Page3 elements 9. Atoms of some elements may have different number of protons in their nucleus producing that are called isotropics.
  • 4. 5 Answer: false Atoms of some elements may have different number of neutrons in their nucleus producing that are called isotopes. Page 3 10. Composite materials are usually designed to display the combination of the component materials. Answer: true Page 3 11. physical and mechanical properties of engineering materials are derived from the type of the interatomic bonding Answer: true Page 4 12. Secondary bonds are some times called intermolecular bonds. Answer: true Page4 Generally electrical thermal conductor due to covalent bond extremely flexible properties once permanent component materials 13. Hydrogen bonds are strong and stable interatomic bonding.
  • 5. 6 Answer: false.hydrogen bonds are strong and stable intermolecular bonding. Page7 14. Anisotropy represents a state in which the properties are the same in all directions. Answer: false isotropy represents a state in which the properties are the same in all directions. Page8 15. Crystalline solids are isotopics because of random arrangement of atoms in all three dimensions. Answer: false Crystalline solids are anisotopics because of random arrangement of atoms in all three dimensions. Page 8 16. There are only two atoms contained along [111] directions for BCC crystal structure. Answer: true Page11 Fix stable same direction Question: fill in the following blank with a suitable word or term.
  • 6. 7 1. Extraction metallurgy is the science that deals with theof metals from earths crust. Answer: mining. Page1 2. The science that deals with the mining of metals from earths crust is called.. Answer: Extraction metallurgy. Page1 3. Thermoset plastics are those polymers which when set into permanent shape by heating, reheat will not.. Answer: soften it. Page2 4. Ceramic materials are characterized by...electrical conductivity. Answer: poor. Page2 5. AL2O3 and SiO2 are considered as .. Answer: ceramic materials. Page2 6. Most of polymers are extremely.. Answer: flexible. Page2
  • 7. 8 7. For the formation of ionic bonding, two kinds of atoms must exist one isand the other is.. Answer: Losing electron, receiving electron. Page5 8. Hydrogen bonding occurs between molecules in which is..bonded to fluorine, oxygen. Answer: covalently Page7 9. Materials are the same in all direction are called.. Answer: isotopic. Page8 10. All metals are solid at room temperature except Answer: mercury. Earths crust mining soften formation occurs except mercury are considered as Question: Explain each of the followings. 1. Ceramic materials are poor electrical and thermal conductors. Answer: because of ionic bond. Page2 and page 5
  • 8. 9 2. What is deriving force behind the bonding mechanism between two atoms and consequently the creation of all kinds of materials? Answer: the bonding mechanism between atoms derives from the desire of atoms to remain in or revert to a stable condition, thus, this stability depends on an atoms ability to maintain eight electrons in its outer most rings, it can achieve stability by one of the following ways: 1) Gaining electrons [to form an ionic bond] 2) Sharing electron [to form a covalent bond] 3) losing electrons [to form a metallic bond] Page 4 3. What is the main objective in designing of composite materials? Answer: A composite is designed to display the combination of the best characteristic of each of the component materials. Page3 4. Is it true that all mechanical properties of engineering materials depend on the type of interatomic bonding. Discuss it. Answer: The type of interatomic bonding affects mechanical and other physical properties of engineering materials which depend on the valence electron of the outer most rings around the nucleus, since the atoms composing a solid material are bonded to each other y means of these outer most valence electrons. Page 4 5. iquefaction of some inert gases at subzero temperature. Answer: dispersion bond causes inert gases to liquefy. Page 6
  • 9. 10 6. Metals are good conductors of electricity. Answer: the movement of free electrons means that metallic bonded materials have good thermal and electrical conduction. Page 6 7. Polymeric materials have low densities. Answer: polymers bonds are non-crystalline but they are direction bond. Page 6 8. Non-crystalline solids are usually referred to be anisotropic. Answer: because of random arrangement of atoms or molecules, non- crystalline solids are usually referred to be anisotropic. 9. The attraction that exist between water molecules. Answer: hydrogen bonding occurs in which hydrogen (H) is covalently bonded to oxygen in H2O,in this case the single electron of hydrogen is shared with the other atom, thus, the hydrogen end of the bond is essentially a positively charged bare proton as shown below:
  • 10. 11 Page7 referred random arrangement Liquefaction charge Inert subzero temperature density consequently creation kinds desire remain in revert stable condition ability maintain outer most rings achieve form Question: What makes the metals to be different from non metallic material? Answer: metallic bonding makes the metals to be different from non metallic material.
  • 11. 12 Question: Distinguish between dispersion and hydrogen bonds. Answer: dispersion bond is temporary and very weak interatomic or intermolecular bonding between atoms or moleculars that electrically not symmetric as shown below. But hydrogen bond is the strongest secondary intermolecular bonding type, it is especial case of polar molecular bonding . it occurs between molecules in which hydrogen (H) is covalently bonded to fluorine (F)
  • 12. 13 ,asin HF, oxygen as inH2O ..etc is such case like this one , the single electron of hydrogen is shared with the other atom, thus, the hydrogen end of the bond is essentially a positively charged bare proton as shown below: Unit cells Question: answer by true or false and then rewrite the false statements in the correct form. 1. the number of atoms per one FCC unit cell is 6atoms/unit cell. Answer: false the number of atoms per one FCC unit cell is 4atoms/unit cell. Page 12 2. In BCC crystal structures the lattice constant (a) can be expressed as a=2D/3 , where D is the atomic diameter in angstrom. Answer: true Page12 3. Allotropy is also called polymorphism and could happen due to temperature and pressure.
  • 13. 14 Answer: true Page13 4. In HCP crystals structures the lattice constant (a) is related to the atomic radius R through the equation.. Answer: a=2R page 13 5. Crystals of high coordination number CN are said to be closely packed crystals. Answer: true Page14 6. Miller indices of planes are represented as [hkl]. Answer: false Miller indices of planes are represented as (hkl). Page16 7. The plane (1010)in HCP crystals is called basal plane. Answer: false the plane (0001) in HCP crystals is called basal plane. Page 19 8. Atomic packing factor APF is defined as the number of atoms per unit area. Answer: falseplaner density is define