Micro structure and chemical composition of building materials 1.01 Flashcards
first presentation
Name the 3 organic materials
-timber
-bitumen
-polymers
Name the 3 metallic materials
-steel
-cast iron
-non-ferrous metals
Name 3 inorganic non-metallic materials
-ceramics
-glass
-cement stone
Name 3 composite materials
-concrete constituents
-reinforced concrete
-masonry
What are the properties of timber?
-lightweight
-high strength in tension and compression
-deformability: mostly ductile
-conditionally durable
-limited temperature resistance
What are the properties of bitumen?
-lightweight
-low strength
-ductile
-aging durability
-limited temperature resistance, depends strongly on properties
What are the properties of polymers?
-lightweight
-high strength in tension and compression
-deformability: mostly ductile
-aging durability
-limited temperature resistance, depends strongly on properties
What are the properties of steel?
-heavy
-high strength in tension and compression
-ductile and formable
-prone to corrosion
-limited temperature resistance
What are the properties of cast iron?
-heavy
-high strength in tension and compression
-ductile and formable
-higher corrosion resistance
-limited temperature resistance
What are the properties of non-ferrous materials?
-“lighter”
-high strength in tension and compression
-ductile and formable
-higher corrosion resistance
-limited temperature resistance
What are the properties of ceramics (natural stones)?
-mostly heavy
-high compressive strength
-brittle, not formable
-mostly durable
-durable temperature resistance
What are the properties of glass?
-heavy
-high compressive strength (+fibers=high tensile strength)
-brittle, not formable
-durable
-fire protection glass temperature resistance
What are the properties of hydraulic binder material (cement)
-mostly heavy
-high compressive strength
-brittle, not formable
-mostly durable
-temperature resistance depends on the design
Define a crystalline material
- Highly ordered atoms or basic modules
- Three-dimensional arrangement in lattice
- High symmetry
- Typical unit cells
- Clear identification possible
- Short and long structural arrangement
Properties:
defined melting point, mostly not transparent, isotropic or anisotropic
Examples:
Metals, ceramics, most natural stones, silicates
Define a amorphous material
- No ordered atoms or molecules
- No symmetry in structure, chaotic system
- Solidified or frozen glassy structure
Properties:
No defined melting point, softening over a wide range of temperature
often transparent, isotropic
Examples:
glass, many polymers
What’s a unit cell?
smallest repeating crystalline unit
How many atoms and what density does a Simple Cubic crystal system has?
1 atom/unit cell
52.36% density
How many atoms and what density does a Cubic Body Centered crystal system has?
2 atoms/unit cell
68.08% density
How many atoms and what density does a Cubic Face Centered crystal system has?
4 atoms/unit cell
74.05% density
Name the 3 crystal systems and packing density
-simple cubic packing
-Face- centered cubic packing
-hexagonal packing
Name two materials with natural porosity
pumice and foamed lava
What is an artificial material with natural porosity?
cement stone
Define porosity
volume in an object that is not composed of solids.
Name 3 classifications of pore sizes
-nanopores
-Micropores
-mesopores
-macropores
What’s total porosity (TP)?
fraction of the total volume that is occupied by pores. The porosity is further subdivided into open porosity and closed porosity.
What’s pore size distribution? (PSD)
fraction of total pore volume in which the pores lie within a stated size range. It can be expressed either in integral or differential form.
What’s specific surface of pores (SS)?
the accessible surface area contained in unit mass of volume of solid and can, in principle, be calculated using total porosity and pore size distribution or indirectly from analytical techniques
What type of foamed polymers are better for temperature isolation?
materials with close cells porosity
What type of foamed polymers are better for sound isolation?
materials with open cells porosity
