METALS Flashcards
- is a soft , nonmagnetic silvery metal
- characterized by its light weight
- low melting point
- high thermal and electrical conductivity (surpassed only by silver and copper)
- moderately high coefficient of expansion
ALUMINUM
- is easily worked: can be hot or cold rolled, extruded, forged, pressed, drawn, molded, stamped, bent and shaped.
- can be riveted, bolted, welded, brazed and soldered
ALUMINUM
In architectural work practically all fabricated forms of aluminum are used
-rod
- bar
- extrusion
- casting
- sheet
- strip, etc.
Is the process of shaping
material by forcing it to
flow through a shaped
opening in a die.
EXTRUSION
(Extrusion)
these products are not fabricated from pure aluminum but in alloy combination with _________________(8) in small quantities to give strength and other desirable characteristics but often reduces its corrosion resistance.
iron, silicon, copper, manganese, magnesium, zinc, chromium and nickel
is a term applied to
certain aluminum products,
refers to the protective coating
(cladding) applied, primarily for
corrosion resistance, to thin
sheets of an alloy whose
corrosion resistance has been
decreased by the constituents
added to give strength and
other characteristics.
Alclad
_________ improves the appearance of the alloy. This thin, integral cladding usually consists of pure aluminum, magnesium silicide, or zinc alloys, with or without manganese.
Cladding
used for roofing,
flashing, gutter, etc
ALUMINUM SHEET AND
STRIP
rolled to a thickness of 0.005” , used mainly for thermal insulation and vapor barriers. It may serve also as a surface finish material when laminated to various sheet and board materials. In this form it also supplies additional insulation value
to the sheet or board.
ALUMINUM FOIL
This is rigidized sheet fabricated of special aluminum alloys specifically developed for this purpose. It usually consists of an aluminum alloy core of one type clad with another, highly corrosion-resistant aluminum roofing and siding
CORRUGATED ALUMINUM
.
When aluminum is used as a
structural material, important
factors, arising from its physical
and chemical characteristics,
are considered:
- Aluminum can be extruded;
- Very corrosion resistant aluminum alloys are
available;
____________ is very lightweight material, hence aluminum girders and columns show increased efficiency with large bay spacing. However, because the modulus of elasticity of aluminum alloys is lower than steel, its means that buckling is a possibility and should always be checked.
STRUCTURAL ALUMINUM
These are generally fabricated from extrusions and rolled shapes
ALUMINUM DOORS AND WINDOWS.
are pre-fabricated units, generally manufactured:- using dimensions of modular and non-modular window-width for building exterior, and- in 600mm, 900mm, and 1200mm widths for interior partitions and dividers.
ALUMINUM PANELS AND SANDWICH PANELS
A sandwich panel comprises a system of construction called ___________
A cellular core of aluminum or other material has
a skin of aluminum applied and bonded to both
sides, thereby forming a unified whole in which all
the components work as one.
skin construction
Many kinds of rods, bars, pipes, railings, fittings, and special shapes are manufactured as stock items for use in ornamental design of railings, grilles, screens, etc.
Ornamental aluminum
are used for fencing, particularly chain link fencing and insect screening.
Aluminum mesh and wire cloth
obtained by grinding polishing, scratching, sandblasting, embossing, or other treatment of the surface to achieve a desired effect or to provide a base for other finishes.
Mechanical finishes
based on chemical reactions
with the aluminum surface to achieve one of the
following results:
(a) etching, cleaning, or polishing
(b) oxidizing the surface with aluminum or other
metallic oxides
Chemical finishes
(chemical finish)
____________of the surface to remove any oxide film or surface irregularity and provide a design, a clean surface texture, or a polished effect;
etching, cleaning, or polishing
(chemical finish)
oxidizing the surface with ____________________ that protect the surface or serve as a base for subsequent treatment, or both. Chemical finishes permit only limited colors that are not as satisfying as the color films obtained on
electrolytically-applied (anodized) oxide films
aluminum or other metallic oxides
Commonly referred to as anodized finishes, these finishes are based on the specific ability of aluminum to develop a protective coating of oxide on its surface. The coating formed may be transparent or opaque.
. It is hard, yet when colored finishes are
desired, it is porous enough to absorb dyes until
the final treatment which seals the surface.
Of the colors used in anodic treatments, architectural gold has proven to be one of the most stable from the standpoint of fade resistance. Others are blue and, more recently, brown and black
Electrolytic finishes
Types of aluminum:
- ALUMINUM SHEET AND STRIP
- ALUMINUM FOIL
- CORRUGATED ALUMINUM
- STRUCTURAL ALUMINUM
- ALUMINUM DOORS AND WINDOWS
6.ALUMINUM PANELS AND SANDWICH PANELS
7.Ornamental aluminum - ALUMINUM MESH AND WIRE CLOTH
Aluminum can be covered with a protective or decorative film or another metal,
usually by electrodeposition. In the case of
copper and nickel, the coating should be
complete and unbroken; otherwise there will be
galvanic action which is destructive to aluminum
Electroplating
This finish forms a hard, resistant surface. It is available in a broad color range that creates a different feeling in that colors are glassy, whereas anodic color is metallic in nature
Porcelain or Vitreous Enamel
________ can be applied as finishes to aluminum surfaces that have been prepared by a suitable chemical treatment finish. Lead based _____ must not be used on aluminum.
Paint
TYPES OF ALUMINUM FINISHES:
Mechanical finishes
Chemical finishes
Electrolytic finishes
Electroplating
Porcelain or Vitreous Enamel
Paint
- tough, malleable silvery-white metal that is soft and ductile as copper
- it is easily magnetized
- is the most magnetically permeable of the metals
- it oxidizes rapidly in air and is readily attacked by most acids.
- can be hardened by heating and sudden cooling
- and made more pliable or more workable by heating and slow cooling.
- At very low temperatures is very brittle
- at red heat it is soft, and
- at white heat it can be welded.
IRON
The commercial form in which iron is first prepared is _____________.
This impure form which contains 3% to
4% carbon and varying amount of phosphorous, silicon, sulfur, and manganese, is the starting point from which all other kinds of iron and iron alloys (or steel) are produced.
crude or pig iron
The key to the various types of iron and steel is the
carbon-iron relationship.
- is an iron-carbon alloy that contains more than
1.7% carbon - is poured while molten into forms
- it can be easily cast into any shape, but it is too hard and brittle to be shaped by hammering, rolling, or pressing.
Cast Iron
is used in the architectural field mainly for piping and fittings, ornamental ironwork, hardware, as the base metal for porcelain enameled plumbing fixtures, and for miscellaneous casting such as floor and wall brackets for railings, vents, circular stairs manhole covers, and gratings.
Cast Iron
________ find their largest use in heavy machinery and industry because it has significant compressive strength and the ability to absorb energy and stop vibration
Cast irons
- is soft, malleable, tough, fatigue
resistant, and resistant to progressive corrosion. - It has good machinability and can be forged, bent, rolled, drawn, and spun. It can be welded by any of the commonly used procedures. It is available in the form of pipes, plates, sheets, special shapes, and bars.
Wrought Iron:
________ is now used in the architectural field primarily in the form of genuine ________ pipe, chain, sheet, and ornamental ironwork.
_________ pipe is used extensively for plumbing, heating, and air conditioning where a corrosion-resistant, tough, durable material is required. Because it is intrinsically related to classical architecture and requires high skilled craftsmanship, this work today is used only in furniture, railing, fences, grilles, and small decorative objects
Wrought iron
The word “________” refers usually to plain carbon steels which is defined as alloys of iron and carbon which do not contain more than 2% carbon and which are made in malleable or ingot form.
steel
________ can be wrought, rolled, cast, and welded, but not extruded.
Carbon steel
This is a medium carbon steel with its carbon content controlled to give both the strength and ductility necessary for its use.
________ is available in angles,
channels, I-beams, H columns, T shapes, Z shapes, plates, round pipe columns, sheet piling, open web joists, and light steel framing shapes.
Structural steel