basic asnt review 3rd Flashcards
fracture is the type of material failure. of the following, which is another type of material failure? (fracture mechanics, low frequency dynamic loading, Permanent deformation, elongation within the Elastic range)
Permanent deformation
which of the following statements best differentiates between a defect and a discontinuity (all discontinuities are defects, all defects will lead to failure if detected, discontinuities can propagate and become defects, discontinuities are external natural boundaries only; Defects are internal flaws )
Discontinuities can propagate and become defects
Nondestructive testing is often differentiated from other measurement Or inspection technique In that
Nondestructive testing involves indirect tests related to some other quality or characteristic of the material
Which of the following describes a function of nondestructive testing (identification and sorting of material, identification of material properties, assuring absence of faults or defects that could cause a part to fail)
All of these
An important basis for the success of fracture control design procedures is
The need to assure that unexpected flaws of some critical size are not present when the component enters service
properly used, nondestructive testing can assist in fracture control by
Providing an accurate evaluation of the number and type of discontinuities that exist in the material
a statement that a particular experiment to produce to .9 probability of detection with a 95% of Confidence level means that
There is a 5% probability that the probability of detection is overstated
The most solid metals and plastics that have reasonable strength at room temperature are called
Allotropic materials
Material properties as used in design, are most frequently determined by
Material testing
Even at the early stages of product planning, nondestructive testing should be considered because (may be required by codes and specifications, the design of the part should permit easy access to critical areas for inspection, the materials selected should be compatible with an nondestructive technique that can accurately evaluate the product)
All of these
Which of the following material properties are of most concern if corrosion resistance is essential (Processing Properties, mechanical properties, physical properties, Chemical Properties )
Chemical Properties
Which of the following is true relative to the comparison of the properties of aluminum based alloys and iron base of alloys (iron has a lower melting point than aluminum, iron can exist in different crystalline structures and it can be controlled by heat treatment, iron can be alloyed to increase its strength whereas aluminum is strongest in its pure state, iron is preferred in load carrying designs but should not be used in any deformation type of manufacturing process)
iron can exist in different Crystalline structures, and its properties can be controlled by heat treatment
Tensile tests are conducted on specimens from a newly developed alloy in order to determine the ultimate Tensile strength of that material. Such tests are called
Destructive tests
A bar that is 12 inches long, 2 inches wide, and 1 inch thick is subjected to a Tensile load acting along the length of the bar of 36,000 pounds. What is the tensile stress within the bar
18,000 PSI
The modulus of elasticity, or Young’s modulus, is related to the materials relative
Stiffness or yield strength
Which of the following materials is typically considered when the application only requires High compressed of strength (Low carbon steel, high carbon steel, cast iron, magnesium )
Cast iron
A fatigue failure can often be prevented by using non destructive testing to
Detect surface discontinuities that could be stress risers
Which of the following tests uses a pendulum to break a specimen that is notched and supported on both ends, with the result of measuring energy absorption (creep test, charpy test, fatigue test, transverse rupture test)
Charpy test
Direct hardness tests provide a measure of a materials ability to resist
Surface and near surface penetration
A particular type of steel has an ultimate strength of 80,000 pounds psi, an elastic limit of 60,000 PSI and a yield strength of 62,000 PSI. An allowable design stress of 20,000 PSI is used, what is the factor of safety based on the ultimate strength
Four
Under ordinary usage, metals exist as
Crystalline solids
The terms of body centered cubic, face centered cubic, and hexagonal close packed all refer to the
Lattice structures that make up unit cells in a solid metallic Structure
the process of returning ductility to a cold work low carbon steel is called
Recrystallization
Many metals exhibit an increase in strength caused by plastic flow beyond elastic limit. This effect is called
Work hardening
When used as an in process treatment, recrystallization can
Improve ductility, refine grains
Process is called all Austenitizing, annealing, normalizing, sphereoidizing are
Approximate equilibrium heat treatment processes
the term of precipitation hardening is often used interchangeably with the term
Work hardening
An NDT to method that has the ability to measure changes in electrical conductivity caused by the effects of heat treatment is
Eddy current testing
Spheroidizing and normalizing have the effect of
Increasing ductility
When Steel has been Quench hardened and then reheated to some point below the lower transformation temperature for the purpose of reducing brittleness, this is called
Tempering
Annealing is usually performed to
Decrease hardness, increase ductility, relieve stresses
Attacks on metals by direct chemical action or electrolysis are called
Corrosion
Metal corrosion that is accelerated when the metal is under loads is called
Stress corrosion
Which of the following may be performed to help prevent corrosion (Stress relieving, anodizing, dipping in molten metal, electroplating )
All of these
factors of safety are often in the range of 2 to 4 because
Provide allowances for unexpected loads or conditions, present problems and assigning effective aircraft, could be reduced with the assurance of NDT techniques that the material was free of discontinuities
the reduction of iron ore, by mixing with coke, limestone, and oxygen for combustion of the coke, is accomplished in
A blast furnace
In the iron and steel making process of, the term pig iron refers to
A high a carbon, low ductility metal that is produced in the blast furnace which can be used to make subsequent types of iron and steel
Which of the following techniques is often used to speed up the steelmaking process (adding large amounts of carbon to the molten metal, reducing the amount of scrap steel that is often added to the molten metal, adding oxygen to the molten metal, converting the old open hearth furnaces into electric furnace )
Adding oxygen to the molten metal
Typically, the highest quality of steel has produced in
An electric furnace
What percentage of carbon is found in steel
Less than 2%
By Which of the following processes is most of the world steel produced
Basic oxygen
An undesirable byproduct of steelmaking process is
Slag
A steel with 40 points of carbon contains
0.4% carbon
Low carbon steel contains approximately
0.06 to 0.25% carbon
Corrosion resistance steels having relatively high percentages of nickel and chromium
Stainless steels
Austenitic stainless steels are paramagnetic; this means that
non magnetic
Which of the following is an advantage of cast steel over wrought steel (Cast steel usually have More mechanical properties than wrought steel, cast steel have more Is tropic properties Then wrought steel, cast steel are more corrosion resistant than Wrought steel , cast steel cannot be heat treated and are thus less expensive to produce )
Cast steel have more isotropic properties then wrought steel
which of the following nonferrous metals is the most important structural material (Copper alloys, nickel alloys, zinc alloys, aluminum alloys)
Aluminum alloys
The heat treatment of aluminum for the purpose of hardening and strengthening
Can produce tensile strengths equivalent to some carbon steels
Which of the following metals has low strength, hi corrosion resistance, and is used largely and die casting operation (Aluminum, magnesium, zinc, manganese)
Zinc
Which of the following metal alloys has a density approximately 2/3 that of aluminum (Magnesium, beryllium, copper, nickel)
Magnesium
monel and inconel are
Nickel alloys
Which of the following metals can be typically used in an as cast state (Aluminum, zinc, steel, iron)
All of these
A high strength, low density, corrosion resistance metal alloy of significance in the aircraft, marine and Chemical Processing industries is
Titanium
Which of the following statements is true concerning plastics following their initial polymerization (Thermoplastics re soften when reheated, thermosetting plastics do not soften, but char and deteriorate when reheated, all plastics are synthetic and contain no natural materials)
Thermoplastic RE soften and an thermosetting plastics do not soften but deteriorate when reheated
based on the strength to weight ratio: plastics and stele
Some plastics, including nylon, may have strengths greater steel
regarding solidification of molten metal in a casting mold, how does cooling take place
In phases having different rates of that produce different types of grain structure in different sections of the casting
In a casting, shrinkage occurs
Before, during, and after the transformation from a liquid to solid
Large voids or porosity in the casting result from
Gas evolution before and during solidification
During the solidification of a casting the shrinkage that occurs
May cause cavities that are enlarged by the evolution of gases
The design of the casting is important because the quality of the finished product can be adversely affected by the
Lack of molten metal to compensate for contraction, location of the gate with reference to either progressive solidification or directional solidification, the location of hotspots in areas of the casting that are isolated by thin sections
That term used to describe the discontinuity in a casting that occurs when molten metal interfaces with already solidified metal with failure to fuse at that interface
Cold shut
The part of the casting where the gate or riser was attached
May provide a concentration point for discontinuities
Risers, feeders, or feed heads in castings serve to provide sources of molten metal to compensate for
Shrinkage
Green sand casting molds include
Sand, clay and water
Small metal supports use to support and positioned cores become part of a casting by fusing with the molten metal. Such devices are called
chaplets
Mold material in the form of inserts that exclude metal flow and form internal Surfaces or passages in a casting are called
Cores
which of the following may cause a discontinuity even though its intended purpose is to prevent shrinkage cavities by absorbing heat from the molten metal (riser, a core, and internal chill, the chaplets)
Internal chill
Which of the following NDT method can be commonly used to inspect castings for core shaft and non fused chaplets and used to determine that all core materials have been removed (Ultrasonic testing, Magnetic particle testing, radiographic testing, eddy current testing)
Radiographic testing
Casting molds made by covering a heated metal pattern with say and that is mixed with particles of thermal setting plastic are called
Shell molds
Permanent molds are most frequently made of
Metal
Another term for precision casting and the lost wax process is
Investment casting
The casting process used to produce hollow products like large pipes and hollow shafts is
centrifugal casting
A casting process used to produce elongated shapes by drawing solidified metal from a water-cooled mold backed by molten metal is
Continuous casting
An assembly that has been created by joining two or more parts by one or more welds is called a
weldment
A general definition of welding describes the joining of two surfaces
In a permanent union established by atom to atom bonds
Of the following which is not a requirement for fusion bonding (melting, atomic closeness, atomic cleanliness, pressure)
Pressure
Metallurgical affects in a weld, such as brain size variation in shrinkage, are similar to those that occur in
Castings
pressure welding can be accomplished with pressure alone, but what else is usually added
Heat
proper brazing depends on numerous factors being controlled. Of the following which is not appropriate (proper joint fit and joint preparation, adequate heat to melt the braze filler, selection of proper braze filler, complete melting of the step metal and a fusion of the braze filler into the base metal)
Complete melting of the step metal and diffusion of the braze filler into the base metal
Soldering, brazing, and braze welding all
Use a process where only the filler metal is actually melted
Due to high temperatures in a rapid rate of cooling, the filler material used in fusion welds
Contains alloys that will help compensate for properties lost during the welding process
The uneven shrinkage and brittle structures that occur due to the rapid cooling of a weld can often be reduced by
Pre heating the weldment prior to welding
After welding, many steel weldment some are heat treated to obtain more uniform properties between the weld and base metal and to relieve stress, which heat treatment method is often used following welding (tempering, normalizing, Spheroidizing, Martensitic aging)
Normalizing
Weldment subject to restraint during welding can develop high residual stresses. Unrestrained weldments can develop (geometric distortion, hi residual stresses, cracking after the weld has cooled)
All of these
Weldments and welds have been known to develop cracks long after cooling but prior to being used in service. What is the principal cause of these cracks
Excessive residual stresses
in arc welding, the electric arc is usually sustained between an electrode it and the
Work piece
Which gases are most frequently used as shielding to provide an inert atmosphere in the vicinity of the weld
Argon, helium and carbon dioxide
When molten metal is transferred from the electrode to the weld zone, it can be shielded from the atmosphere by
The burning of coatings on the welding electrode, maintaining the arc beneath flux powders, the flow of the shielding gas around the arc
The burnout rate and the amount of spattering during the arc welding process can often be controlled by
Selecting the proper electrode polarity
Which of the following welding process these uses non consumable electrode with the arc maintained in an atmosphere of inert gas (gas tungsten arc welding, submerged arc welding, gas metal arc welding, or electro slag welding)
Gas tungsten arc welding
Shielding in the submerged arc welding process is provided by
Granular flux that completely surrounds the arc
Which welding process places the pieces to be welded between electrodes
Resistance spot welding
A welding process that most frequently carried out in a vacuum chamber is called
Electron beam welding
The welding process capable very high intensity and rate of heat transfer is called
Plasma arc welding
The welding process in which the arc is extinguished after melting a slag cover and in which the base metal and copper slides form a sort of moving mold is called
Electro slag welding
In the process of diffusion welding often called the diffusion bonding, the base metal is joined by
Putting it under pressure, at temperatures below the melting point
A slag inclusion can result from which of the following (small pieces of tungsten being dislodged from the electrode, insufficient cleaning of successive passes in the weldment, excessive undercut on intermediate passes in the weldment)
Insufficient cleaning and excessive undercut
Undercut on a weld pass is usually caused by
Poor operator technique
Crater cracks may take the form of a single crack or star shaped cracks and will usually be found
Anywhere along a weld where the welding was stopped and restarted
The principal purpose of preheat treatment and post heat treatment in welds is to
Neutralize residual stresses and geometric distortion
The most obvious defects in the welding are those associated with structural discontinuity ease in the weld itself. Other conditions that may also be considered as defects are (improper well dimensions and profiles, base metal your regularity ease that have been enlarged, structurally sound welds but those with inadequate properties caused by errors in filler metal)
All of these
Up in a V groove weld made in multiple passes and not clamped or restrained, typical warping would take place in which direction
Surface is A and B would be raised due to the contraction of the weld metal
Cracks in the weld metal are primarily of which three types
longitudinal, transverse and crater
Deformation of metals provides a number of advantages. What would be one disadvantage
Deformation processes increase the probability of defect formation
If the advantageous effect of recrystallization depend upon
Up the rate of deformation, and the temperature at which deformation takes place
Wrought products invariably exhibit
Directional properties
During the steelmaking process, the large number of faults such as flag, porosity, and shrinkage cavities exist in the top of the ingot. These discontinuities are
Removed by cropping up to One third off the top of the ingot
Discontinuities can be reduced in severity by the closing and welding of voids and the breaking up and the elongation of inclusions by which of the following processes
Hot working
Which of the following would have the least ductility (cold rolled steel plate, hot rolled steel plate, gray cast iron, hot rolled aluminum plate)
Gray cast iron
And NDT technique best suited to locating discontinuities caused by inclusions rolled into steel plate is
Ultrasonic testing
What is true concerning a deformation process involving cold working and hot working
Cold working usually follow hot working
Machinability and fatigue resistance are improved in most metals that have been
Cold worked
NDT is often used just following hot and cold working operations to
assure that further operations are not performed on material that contains defects that could cause rejection of the manufactured part
Slabs, blooms and billets are
The shapes that the ingot is rolled into prior to a variety of secondary operations
Cold rolling sheet steel usually begins with a material that
Has been previously hot rolled two dimensions close to the size of the finished product
Before cold finishing operations can be done on a hot rolled materials, cleaning is often done by immersing the hot rolled material in acid baths in a process called
Pickling
The millwork process performed principally on flat products and bars that improves hardness, strength, surface finish and dimensional accuracy is
Cold working usually follow hot working
Most steel pipe is produced by forming and
Welding
Welding most seamless two being made without welds is produced by
Piercing
A process that requires the use of large powerful equipment that forms ductile material into a wide variety of long length uniform across sectional shapes best describes
Extrusion
The mill working process used most to form metals into three dimensional shapes is
Forging
which of the following product forms is generally selected for high strength in control property directionality (castings, extrusions, hot rolled flat stock, forgings)
Forgings
Powder metallurgy provides two unique advantages in metals processing. One is the capability to produce shapes and objects of refractory metals that are extremely difficult or impractical to melt; the other is to
Produce metal shapes with controlled porosity
A major purpose of pressing the metal powders during metallurgy processing is to
Compact the powders into mechanical and atomic closeness
In the powder metallurgy process, sintering is
In most cases, a fully solid state process
Powdered metallurgy products cannot
Attain 100% of theoretical density
Which of the following is an application for powdered metal products (Cemented carbide cutting tools, tungsten rocket nozzles, oil impregnated bushings)
All of these
Machines designed to hold a cutting tool and a work piece and establish a suitable set of motions between them to remove material are called
Machine tools
In describing machine ability of three different measurements are generally considered on a relative basis. These are
Surface finish, power consumption and tool life
When used with respect to machine tools, the acronym NC means
Numerical control
Metals commonly applied to other metals by electroplating are
The use of numerical control systems applied to conventional types of machining operations
Plastics processing involving thermoplastics and thermosetting may be processed by
Molding, casting and extrusion
Reinforced plastic molding involves use of
Thermosetting plastics and by fibrous reinforcement material
The mechanism of adhesion combines mechanical interlocking
Interatomic forces
The major difference between materials classified as composites and those classified as mixtures is
Mixtures are a type of composite with random orientation and shape of the constituents
The acronym EDM refers to
Electrical discharge machining
A machining process that involves electrolyte, electrical supply and a chemical process is called
Electrochemical machining
The process use for shaping metals by chemical dissolution only, with selective removal accomplished by masking is called
Chemical milling
The machining process involving high frequency transducer any slurry removal is called
Ultrasonic machining
A process that is the reverse of electrochemical machining and that is the basis for electroplating is called
Electro forming
A cutting operation that has the ability to cut through thickness is of over 3 feet of steel and is commonly used to remove surface defects on castings and forgings by scarfing is called
oxy acetylene cutting
Carburizing and flame hardening are examples of
Case hardening processes
Are there any other processes following the service finishing
Not typically
which nondestructive test would provide the best results in measuring the case depth on a case hardened part
Eddy current testing
Coatings are often applied to protect a material; their thickness can frequently be determined by which nondestructive testing
Eddy current testing
The best and most economical cleaners used for removal of oil and grease are
Petroleum solvents
Some materials and, such as aluminum, are corrosion resistant by
Virtue of the immediate oxidation of newly exposed surfaces
An advantage of electrostatic spraying is that
The material being sprayed is directly attributed to all of the surfaces to be covered, there is less waste due to over spray material, there is more uniform coverage of the surfaces
A corrosion protection material commonly applied to steel by hot dipping and galvanizing is
Zinc
Metals commonly applied to other metals by electroplating are
Nickel, chromium and cadmium
A process that converts the base metal surface to and oxidize barrier layer of very small porous is called
Anodizing
The anodized surface on aluminum
Can produce a high background during a penetrant test
Eight technique for the inspection of manufactured products that utilizes the selection of certain percentage of parts for inspection is called
Random sampling
Implied in sampling inspection is
A willingness to sometimes accept defective products
A process control chart based on the means and ranges of measurements taken on periodic Samples requires the measurement to be taken of
Variables
Frequently, dimensions are permitted to vary within specified limits. These variations are called
Tolerances
Measurements are classified as being either
Comparative or absolute
A vernier measurement permits
Accurate interpolation Between major divisions on a measuring device
Indicating gauges are usually used in applications that provide
Comparative measurements
Which of the following measurement tools to use the principle of light wave interference to checked surface flatness
Optical flat
Gauges such as plug a gauges, rain gauges, profile gauges, thread gauges, radius gauges, are all types of
Fixed gauges
Devices that Show magnified reflected or profile images of the work piece on a frosted glass screen are called
Optical Comparators
