120102i Hardfacing Flashcards
What does the term hardfacing mean?
a) the application of an alloy that assists corrosion
b) to weld together parts that have been quenched
c) to apply a layer of material that combats wear
d) to apply material that is difficult to use
c) to apply a layer of material that combats wear
Machinery parts that are subjected to wear can have their service life prolonged by:
a) welding with alloy electrodes.
b) hardfacing the wear surface.
c) repairing the parts often.
d) using the equipment sparingly.
b) hardfacing the wear surface.
What is a major advantage of hardfacing?
a) Worn parts with high replacement costs can be reclaimed.
b) Hardfacing filler alloys are cheap and easy to apply.
c) Any hardfacing alloy can be used with any welding process.
d) The very hard alloys can also withstand high impact loading.
a) Worn parts with high replacement costs can be reclaimed.
Which arc welding process is very popular for hardfacing because of its low
equipment cost, versatility and general ease of application?
a) GMAW
b) SMAW
c) GTAW
d) FCAW
b) SMAW
Which method of hardfacing process is the slowest?
a) SMAW
b) FCAW
c) GMAW
d) GTAW
d) GTAW
What is a disadvantage of the FCAW surfacing process as compared to GMAW surfacing?
a) It produces slag, which may have to be removed.
b) Alloys cannot be added to the wires.
c) The cored electrode can only be used on a small radius.
d) The equipment is much more expensive.
a) It produces slag, which may have to be removed.
What is the advantage of the MCAW surfacing process compared to the FCAW surfacing process?
a) The deposition rates are similar.
b) Special equipment is required.
c) Alloys cannot be added to the wires.
d) It produces little to no slag.
d) It produces little to no slag.
Which arc welding surfacing method uses high currents and high deposition rates, leaves no spatter and emits no harmful ultraviolet radiation?
a) SMAW
b) OAW
c) SAW
d) FCAW
c) SAW
Which is true of the oxy fuel gas hard surfacing process?
a) You can surface only large areas.
b) The base metal does not have to be clean.
c) It has a higher deposition rate than arc surfacing processes.
d) It has low base metal dilution.
d) It has low base metal dilution.
Which statement describes thermal spray surfacing?
a) The flame carburizes the surface so that the rod can be melted onto it.
b) The constricted arc is forced between the electrode and the workpiece.
c) The electrode is continuous, and the arc is covered with a flux.
d) It heats a metallic or non-metallic material and propels it toward the object.
d) It heats a metallic or non-metallic material and propels it toward the object.
A sliding/scraping type of wear that removes metal by gouging or grinding is called:
a) erosion.
b) abrasion.
c) corrosion.
d) impact.
b) abrasion.
A gouging type of wear that washes away or grooves out the metal surface is called:
a) corrosion.
b) oxidation.
c) erosion.
d) abrasion.
c) erosion.
A seizing or galling type of wear that rips and tears out portions of a metal surface is called:
a) abrasion.
b) metal to metal.
c) erosion.
d) compression.
b) metal to metal.
The type of wear that pits, perforates and eventually dissolves metal is called:
a) thermal shock.
b) abrasion.
c) erosion.
d) corrosion.
d) corrosion.
A special form of corrosion that results in the crumbling or flaking off of a metal surface is called:
a) erosion.
b) oxidation.
c) metal to metal.
d) compression.
b) oxidation.
A cracking/splitting type of wear caused by rapidly exposing metal parts to rapid heating and cooling cycles is called:
a) thermal shock.
b) impact.
c) abrasion.
d) metal to metal.
a) thermal shock.
A squeezing type of wear usually caused by the imposition of a heavy static load on the surface of a metal is called:
a) abrasion.
b) impact.
c) compression.
d) corrosion.
c) compression.
Which material is the most abrasion resistant of all hardfacing materials?
a) tungsten carbide
b) chromium carbide
c) austenitic manganese
d) austenitic stainless steel
a) tungsten carbide
Which hardfacing material can be ferrous or non-ferrous?
a) tungsten carbide
b) chromium carbide
c) austenitic manganese
d) austenitic stainless steel
b) chromium carbide
These hardfacing materials, alloyed with 5% - 12% chromium, are probably the most widely used.
a) semi-austenitic
b) austenitic manganese
c) austenitic stainless steel
d) martensitic stainless steel
a) semi-austenitic
These hardfacing materials, which are work-hardenable, are well suited for impact loading.
a) tungsten carbide
b) chromium carbide
c) austenitic manganese
d) martensitic stainless steel
c) austenitic manganese
For best results, the deposits with these materials should be two or more layers thick.
a) tungsten carbide
b) chromium carbide
c) martensitic stainless steel
d) heat-treatable steels
c) martensitic stainless steel
Which material results in a deposit that is hard if cooled quickly or soft and tough if cooled slowly?
a) tungsten carbide
b) heat-treatable steels
c) austenitic manganese
d) copper alloys
b) heat-treatable steels
Which hardfacing material is used for sliding metal-to-metal contact and for
corrosion resistance applications?
a) chromium carbides
b) austenitic manganese
c) heat-treatable steels
d) copper alloys
d) copper alloys
What problem can result from the deep penetration characteristics of some arc welding processes?
a) The hardfacing metal may dilute with the base metal.
b) Metal chunks may break away from the base metal.
c) The parts may become hardened by heat treatment.
d) With preheat, underbead cracking always results.
a) The hardfacing metal may dilute with the base metal.
Which term describes the breaking away of the weld metal from the base metal?
a) dilution
b) distortion
c) galling
d) spalling
d) spalling
What is one method you could use to avoid stress failure when hardfacing a part hardened by heat treatment?
a) Use no preheat.
b) Quench in water right after welding.
c) Avoid interruptions during welding.
d) Quench in oil and cover with a blanket.
c) Avoid interruptions during welding.
