ASNT Level 3 Basic Materials & Processes
Low carbon steel contains approximately:
0.06 to 0.25% carbon
A steel with 40 points of carbon contains:
0.4 % carbon
The design of the casting is important because the quality of the finished product can be adversely affected by all of the following.
1. Lack of molten metal to compensate for contraction. 2. Location of gate with reference to either progressive solidification or directional solidification. 3. The location of hot spots in ares of the casting that are isolated by thin sections.
A bar that is 2 in. long, 2 in. wide and 1 in. thick is subjected to a tensile load acting along the lenght of the bar of 36000 lbs. What is the tensle stress within the bar?
18000 psi.
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, the term pig iron refers to:
A high carbon, low ductility metal produced in the blast furnace that can be used to make subsequent types of iron and steel.
Implied in sampling inspections is
A willingness to sometimes accept defective products
A vernier measurement permits
Accurate interpolation between major divisions on a measuring device
Which of the following techniques is often used to speed up the steel making process?
Adding oxygen to the molten metal.
The term"precipitation hardening" is often used interchangeably with the term:
Age hardening.
Which of the following nonferrous metals is the most important structural material?
Aluminum alloys
Typically, the highest quality of steel is produced in:
An electric furnace.
What is a S-N curve?
An endurance limit curve diagram.
A process that covers the base metal surface to an oxidized barrier layer of very small porous cells is called
Anodizing
Crater cracks may take the form of a single crack or star-shaped cracks and will usually be found
Anywhere along the weld where the welding was stopped and restarted.
Processes called austenitizing, annealing, normalizing and spheroidizing are:
Approximate equilibrium heat-treatment process.
Which of the following gases are most frequently used as shielding to provide an inert atmosphere in the vicinity of the weld
Argon, helium and carbon dioxide.
Powdered metallurgy products cannot
Attain 100% of theoretical density
By which of the following process is most of the world's steel produced:
Basic oxygen.
In casting, shrinkage occurs:
Before, during and after the transformation from liquid to solid
Which of the following terms describe operations that bend, stretch and shape ,metals into three dimensional shapes with significant plastic flow and deformation
Bending. Forming. Drawing.
Which of the following statements is true regarding plastics processing
Both thermoplastics and thermosetting plastics may be processed by molding, casting and extrusion
Some materials, such as aluminum, are corrosion resistant:
By virtue of the immediate oxidation of newly exposed surfaces.
The anodized surface on aluminum
Can produce a high background during a penetrant test
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 materials cannot typically be used in the as-cast state?
Carbon
Carburizing and flame hardening are examples of
Case hardening process
Which of the following materials is typically considered when the application only requires high compressive strength?
Cast iron.
Which of the followingis an advantage of cast steel over wrought steels?
Cast steels have more isotropic properties than wrought steel.
Metallurgical effects in a weld, such as grain size variation and shrinkage, are similar to those that occur in
Castings
Which of the following is an application for powdered metal products
Cemented carbide cutting tools and dies. Tungsten rocket nozzles. Oil-impregnated bushings.
A casting process used to produce hollow products like large pipes and hollow shafts is
Centrifugal casting
Small metal supports used to suport and position cores become part of the casting by fusing with the molten metal. Such devices are called?
Chaplets.
Which of the following tests uses a pendulum to break a specimen that is notched and supported on both ends, with the results of measuring energy absorption?
Charpy test.
The process used for shaping metals be chemical dissolution only, with selective removal accomplished by masking areas where metal is not to be removed, is called
Chemical milling
which of the following material properties are of most concern if corrosion resistance is essential?
Chemical properties.
Which of the following statements is true concerning surface finishing
Cleaning operations are considered to be surface-finishing process. Surface finishing is often performed for corrosion protection. Surface finishing is sometimes performed to improve surface and near surface mechanical properties
The millworking process performed principally on flat products and bars that improves hardness, strength, surface finish and dimensional accuracy is
Cold rolling
The term used to describe a discontinuity in a casting that occurs when molten metal interfaces with already solidified metal with failure to fuse at the interface is:
Cold shut.
Machinability and fatigue resistance are improved in most metals that have been
Cold worked.
Deformation processes
Cold working usually follows hot working.
A major purpose of pressing the metal powders during powder metallurgy processing is to
Compact the powders into mechanical and atomic closeness
Indicating gages are usually used in applications that provide
Comparative measurements
Measurements are classified as being either
Comparative or absolute
Devices that show magnified reflected of profile images of the workpiece on a frosted glass screen are called optical
Comparators
Which of the following statements is true concerning composite materials
Composite materials can be wrapped over metallic materials to increase strength and reduce weight
Which of the following statements is true regarding the electrical conductivity of aluminum alloys?
Conductivity decreases at elevated temperatures.
Due to high temperatures and rapid rate of cooling, the filler material used in fusion welds
Contains alloys that will help compensate for properties lost during the welding process
A casting process used to produce elongated shapes by drawing solidified metal from a water-cooled mold backed by molten metal is
Continuous casting
Which of the following is true regarding solidification of molten metal in a casting mold?
Cooling takes place in phases having different rates that produced different types of grain structures in different sections of the casting.
Brass and bronze are alloys of zinc, tin and a large percentage of:
Copper.
Mold material in the form of inserts that exclude metal flow and thus form internal surfaces or passages in a casting are called:
Cores.
In welding the most obvious defects are those associated with structural discontinuities in the weld itself. Conditions not considered welding process defects are
Corrosion of the structural members
Attacks on metals be direct chemical action and/or electrolysis are called:
Corrosion.
Factors of safety are often in the range of 2 to 4. These factors:
Could be reduced with the assurance of NDT techniques that the material was free of discontinuities.
Under ordinary usage, metals exist as:
Crystalline solids.
Stress-Strain diagram, which of the following ranges indicates the affect of work hardening, to its maximum, caused by plastic flow of the material during a tensile load?
Deformation rate to the ultimate strength
Design engineers are responsible for establishing the function, appearance, quality and cost of a product. Regarding the role of NDT in product design, which of the following is true?
Designer should seek input from NDT personnel to insure all required inspections can be performed.
Tensile test are conducted on specimens from a newly developed alloy in order to determine the ultimate tensile strength of the material. Such tests are referred to as:
Destructive tests.
A fatigue failure can often be prevented by using NDT to:
Detect surface discontinuities that could be stress risers.
Wrought products invariably exhibit
Directional properties.
Which of the following statements best differentiates between a defect and a discontinuity?
Discontinuities can propagate and become defects.
Coatings are often applied to protect a material; their thicknesses can frequently be determined nondestructively by
Eddy current
Which of the following nondestructive tests would provide the best results in measuring the case depth on a case hardened part.
Eddy current
An NDT method that has the ability to measure changes in electrical conductivity caused by the effects of heat treatment is:
Eddy current.
What is Point B on the Stress-Strain diagram where it first starts to curve?
Elastic limit.
The acronym EDM refers to
Electrical discharge machining
A process that is the reverse of electrochemical machining and that is the basis for electroplating is called
Electroforming
A welding process that is most frequently carried out in a vacuum chamber is
Electron-beam 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
Electroslag welding
Most solid metals and plastics that have reasonable strength at room temperature are called:
Engineering materials.
NDT is often used just following hot and cold working operations to
Ensure that further operations are not performed on material that contains defects that could cause rejection of the manufactured part
Welds and weldments have been known to develop cracks long after cooling but prior to being used in service. What is the principal cause for such cracks
Excessive residual stresses
A process that requires the use of large, powerful equipment that forms ductile material into a wide variety of long length, uniform, cross sectional shapes best describes
Extrusion
Gages such as plug gages, ring gages, go/no-go gages, profile gages, thread gages, radius gages, ect., are all types of
Fixed gages
The millworking process used to form metals into three dimensional shapes is
Forging
Which of the following products forms is generally selected for high strength and controlled property directionality
Forgings
Large voids or porosity in a casting result from:
Gas evolution before and during solidification.
Which of the following welding process uses a nonconsumble electrode with the arc maintained in a atmosphere of inert gas
Gas tungsten arc welding
Weldments subject to restrain during welding can develop high residual stress. Unrestrained weldments can develop
Geometric distortion
Shielding in the submerged arc welding process is provided by
Granular flux that completely surrounds the arc.
Which of the following would have the least ductility
Gray cast iron
Cold rolling sheet steel usually begins with a material that
Has been previously hot-rolled to dimensions close to the size of the finished product
Pressure wielding can be accomplished with pressure alone, but what else is usually added
Heat
Deformation of metals provides a number of advantages. Which of the following is an advantage
High duplication accuracy results from most deformation processes. In general, the properties of wrought metals are improved over their cast counterparts. Thin sections can be more economically and more successfully produced than by casting.
Discontinuities with their origin in the original ingot can be reduced in severity by the closing and welding of voids and the breaking up and elongation of inclusions by which of the following processes
Hot working
What are the functions of NDT?
Identifying and sorting of material. Identifying of material properties. Ensuring absence of faults or defects that could cause a part to fail.
When used as in-process treatment, Re crystallization can:
Improve ductility.
A general definition of welding describes the joining of two surfaces
In a permanent union established by atom-to-atom bonds
In the powder metallurgy process, sintering is
In most cases, a fully solid state process
Spheroidizing and normalizing have the effect of:
Increasing ductility.
A slag inclusion can result from which of the following
Insufficient cleaning of successive passes in a multipass weldment.
The mechanism of adhesion combines mechanical interlocking and
Interatomic forces
Which of the following may cause a discontinuity even through its intended purpose is to prevent shrinkage cavities by absorbing heat from the molten metal in the center of the casting:
Internal chill.
Another term for precision casting and lost-wax process
Investment casting
Which of the following is true relative to the comparison of the properties of aluminum-based alloys and iron-based alloys?
Iron can exist in several different crystalline structures and its properties can be controlled by heat treatment.
The term body-centered cubic BCC, face-centered cubic FCC and hexagonal close-packed HCP all refer to the:
Lattice structures that make up unit cells in a solid metallic structure.
On the Stress-Strain diagram, the points represented by E and F would be closer together if the material being tested were:
Less ductile.
What percentage of carbon is found in steel:
Less than 2%
Cracks in the weld metal are primarily of which three types
Longitudinal, transverse and crater.
Machines designed to hold a cutting tool and a workpiece and establish a suitable set of motions between them to remove material from the workpiece are called
Machine tools
Manufacturing process changes raw material by:
Machining.
Which of the following metals alloys has a density approximately two-thirds that of aluminum?
Magnesium.
Material properties, as used in design, are most frequently determined by:
Materials testing.
During the solidification of a casting, the shrinkage that occurs:
May cause cavities that are enlarged by the evolution of gases.
The part of the casting where the gate or riser was attached:
May provide a concentration point for discontinuities.
Of the following, which is required for fusion bonding
Melting. Atomic closeness. Atomic cleanliness.
Permanent molds are most frequently made of
Metal
The major difference between materials classified as composites and those classified as mixtures is that
Mixtures are a type of composites with random orientation and shape of the constituents.
Nondestructive testing is often differentiated from other measurements or inspection techniques in that:
NDT involves indirect tests related to some other quality or characteristic of material.
The principal purpose of preheat treatment and post-heat treatment in welds is to
Neutralize residual stresses and geometric distortion.
Monel and inconel are:
Nickel alloys.
Metals commonly applied to other metals by electroplating are
Nickel, Chromium and Cadmium
Which of the following statements is true concerning honeycomb
Nonmetallic honeycomb derives high strength and rigidity from a structural combination of relatively weak, thin, lightweight materials
After welding, many steel weldments 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
Normalizing
When used with respect to machine tools, the acronym N/C means
Numerical control
Which of the following measurement tools uses the principle of light wave interference to check surface flatness
Optical Flat
A cutting operation that has the ability to cut through thickness of over 0.9 m 3 ft of steel and is commonly used to remove surface defects on castings and forgings by scarfing is called
Oxyacetylene cutting.
Fracture is a type of material failure. Of the following which is another type of material failure?
Permanent deformation.
The best and most economical cleaners used for removal of oils and greases are
Petroleum solvents
Before cold finishing operations can be done on hot-rolled materials, cleaning is often done by immersing the hot rolled material in acid bath in a process called
Pickling
Most seamless tubing made without welds is processed by
Piercing
The welding process capable of very high intensity and rate of heat transfer is
Plasma arc welding
Undercut on a weld pass is usually caused by
Poor operator technique.
The uneven shrinkage and brittle structures that occur due the rapid cooling of a weld can often be reduced by
Preheating the weldment prior to welding
Powder metallurgy provides two unique advantages in metal 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
Proper brazing depends upon numerous factors being controlled.
Proper joint fit-up and joint prep. Adequate heat to melt the braze filler metal. Selection of proper braze filler metal.
If properly used, NDT can assist in fracture control by:
Providing an accurate evaluation of the number and type of discontinuities that exist in a material .
In the process of diffusion welding, often called diffusion bonding, the base metal is joined by
Putting it under pressure at temperatures below the melting point
Which of the following NDT methods can be commonly used to inspect castings for core shift and nonfused chaplets and used to determine that all core materials have been removed?
Radiographic testing
A technique for the inspection of a manufactured products that utilizes the selection of a certain percentage of parts for inspection is called
Random sampling
In drawing and deep drawing, the final shape often can be completed in a series of draws, each successively deeper. What process performed between draws might effectively reduce the number of draws required
Recrystallization.
The process of returning ductility to cold-worked low-carbon steel is called:
Recrystallization.
Annealing is usually performed to:
Release stress.
During the steel-making process, a large number of faults such as slag, porosity and shrinkage cavities exit in the top of the ingot. These discontinuities are
Removed by cropping up to one-third off the top of the ingot.
Green sand casting molds include:
Sand, clay and water.
The burn-off rate and amount of spattering during the arc welding process can often be controlled by
Selecting the proper electrode polarity
Manufacturing is a term that refers to processing that starts with raw material in bulk form and is concerned mainly with processing the raw material in a manner that changes its:
Shape.
Casting and molds made by covering a heated metal pattern with sand is mixed with particles of thermosetting plastic are called
Shell molds
Risers, feeders, or feed heads in casting serve to provide sources of molten metal to compensate for:
Shrinkage.
An undesirable byproduct of steel making processes is:
Slag
Thermal conductivity of a metal is an important factor to consider in making quality weldments because
Some metals, such as stainless steel, have low conductivity, which results in weld defects caused by localized overheating.
Based on the strength to weight ratio:
Some plastics, including nylon, may have strengths greater than some metals.
Spinning can be used to form
Spherical tank halves
Corrosion resistant steels having relatively high percentages of nickel and chromium are called
Stainless steel
The modules of elasticity, or Young's modules, is related to the material's relative:
Stiffness and yield strength.
Metal corrosion that is accelerated when the metal is under a loads is called:
Stress corrosion.
Which of the following does not help to prevent corrosion:
Stress relieving.
Direct hardness test provide a measure of a material's ability to resist:
Surface and near-surface penetration.
In describing machinability, three different measurements are generally considered on a relative, if not quantitative, basis. These are
Surface finish of the material achievable, power consumption required to remove a given volume of material and expected tool life
Among other things, the advantageous effects of recrystallization depend upon the
Temperature at which deformation takes place.
The design of the casting is important because the quality of the finished product can be adversely affected by all of the following except:
Temperature of the mold immediately prior to casting.
When a 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.
When molten metal is transferred from the electrode to the weld zone, it can be shielded from the atmosphere by all of the following
The burning of coatings on the welding electrode. Maintaining the arc beneath flux powders. The flow of a shielding gas around the arc.
Even at the early stages of product planning, NDT should be considered because:
The design of the part should permit easy access to critical areas for later inspection.
All of the following statements concerning electrostatic spraying are true
The material being sprayed is directly attracted to all of the surfaces to be covered. there is less waste due to oversprayed material. There is more uniform coverage of the surfaces.
Austenitic stainless steels are paramagnetic; this means that:
The material has a very low permeability.
An important basis for the success of fracture control design procedures is:
The need to ensure that unexpected flaws of some critical size are not present when the component enters service.
Slabs, blooms and billets are
The shapes that the ingot is rolled into prior to a variety of secondary
Most new developments in sheet metal forming typically use nonconventional energy sources. What is a common feature of these processes?
The use of energy sources that release large amounts of energy in a very short time.
Which of the following can result in economical setup and reduced machine time with an increase in repeatability and accuracy for variety of machining operations
The use of numerical control systems applied to conventional types of machining operations
A statement that a particular experiment produced a 0.9 probability of detection with a 95% confidence level means that:
There is a 5% probability that the probability of detection is overstated.
Reinforced plastics molding involves use of
Thermosetting plastics and fibrous reinforcement materials
Which of the following statements is true concerning plastics following their initial polymerization.
Thermosetting plastics do not soften, but char and deteriorate when reheated.
A high-strength, low density corrosion resistant metal alloy of significance in the aircraft, marine and chemical processing industries is:
Titanium.
Frequently, dimensions are permitted to vary within specific limits. These variations are called
Tolerances
An NDT technique best suited to locating discontinuities caused by inclusions rolled into steel plate is
Ultrasonic testing.
Soldering, brazing and braze welding all
Use a process where only the filler metal is actually melted
A process control chart based on the means and ranges of measurements taken on periodic samples requires the measurement to be taken of
Variables
Most steel pipe is produced by forming and
Welding
An assembly that has been created by joining two or more parts by one or more welds is called
Weldment
Many metals exhibit an increase in strength caused by plastic flow beyond the elastic limit. This effect is called:
Work hardening.
In arc welding the electric arc is usually sustained between an electrode and the
Workpiece.
A corrosion protection material commonly applied to steel by hot dipping and galvanizing is
Zinc.
Which of the following metals has low strength, high corrosion resistance and is used largely in die casting operations?
Zinc.