RM metal id chart

 We have made maintenance welding easier than ever…“What is the base metal?” is often the toughest challenge a maintenance welder has to face. Using this chart along with a file, magnet, and chisel will help answer this question and lead to the proper electrode selection.

STEELS
TEST/METAL LOW CARBON HI-STRENGTH STEEL HIGH CARBON STEEL
USES Angle, channels, beams, sheet, plates E.G. storage tanks (may also be cast) Wear plates, bars, truck frames, excavator parts, some tanks Tools, axles, springs, spindles
FRACTURES Bright grey Very light grey Very light grey
SURFACE UNFINISHED Dark grey Dark grey Dark grey
SURFACE MACHINED Very smooth bright grey Very smooth bright grey Very smooth bright grey
MAGNETIC Yes Yes Yes
FILE TEST Files easily Files Maybe too hard to file depending on carbon content and heat treatment
CHISEL TEST Continuous chip, smooth edges, chips easily Continuous chip Hard to chip, can be continuous
R&M ALLOY RM 480, XR 1000, RM421 UNA-WELD 1235 XR 1020, UNA-WELD 1235 UNA-WELD 1235
STAINLESS STEELS
TEST/METAL CHROME NICKEL 300 SERIES PLAIN CHROME 400 SERIES
USES Pipings and fittings, duct work, corrosion resistant fabrications, chemical and food processing, paper and pulp industries Cutlery and knives, surgical steel, excellent sharp edge capabilities, high stress fasteners, steam and mild chemicals
APPEARANCE Bright silvery smooth (may be cast) Bright silvery smooth (may be cast)
MAGNETIC No Yes
FILE File but harder than steel May be too hard
CHISEL Continuous smooth bright color
R&M ALLOY 300S STAINMASTER UNA-WELD 1235
HINT: Chrome Nickel 300 Series Stainless is used in 90% of all welded stainless applications due to its ease of weldability.
HIGH NICKEL ALLOYS
TEST/METAL NICKEL CHROME MOLY NICKEL CHROME IRON
DESCRIPTION High strength at room and elevated temperatures, exceptional corrosion resistance against pitting and crevice corrosion Excellent strength and oxidation resistance at high temperatures and retains impact resistance to -140° F
USES Valves, pumps, piping, marine fixtures, petroleum refining, fasteners, pulp and paper, liquor tanks and pickling plants Heat treating equipment, heat treat baskets, furnace and boiler components, scrubbers, food processing, pollution control, petro chemical
MAGNETIC No No
APPEARANCE Looks like stainless Looks like stainless
USE ON All wet corrosion applications All dry corrosion applications
ALLOY RM 3000 RM 3000
NOTE: Pure nickel alloys are magnetic.
COPPER BASE ALLOYS
TEST/METAL PURE COPPER YELLOW BRASS RED BRASS
USES Tubing, buss bars, wiring Decorative items, plumbing faucets, drain covers and traps Plumbing, elbows, small valves, screws, valve stems
APPEARANCE Red Yellow Rosie
R&M ALLOY RM 340 RM 320 RM 320
TEST/METAL PHOSPHOR BRONZE SILICON BRONZE ALUMINUM BRONZE
USES High quality steam valves, gears, some marine hardware Pumps, high strength castings, impellers High strength gears, gears, wear plates, worn wheels, bearings
APPEARANCE More red than yellow Red Fairly yellow
R&M ALLOY RM 320 RM 320 RM 320
  • Aluminum bronze will chip instead of curl when machined and is slightly magnetic.
  • Red brass will curl when machined.
  • Brass will put off white smoke under flame due to zinc content.
  • Copper alloys listed will be nonmagnetic except for aluminum bronze.
  • When possible silver braze copper alloys.
  • Copper melts much slower than brass and bronze.
ALUMINUM AND WHITE METALS
TEST/METAL ALUMINUM MAGNESIUM ZINC DIE CASTING
USES Angles, beams motor housings, boat hulls, marine hardware castings, window frames Aircraft parts (high strengths/light weight) ladders, mortar shells, raised printer plates Carburetor bowls, trophies, ornaments, kirksite dies, housings
WEIGHT About ⅓ weight of iron ⅕ weight of iron About same as iron
ACID TEST Nitric acid won’t react White vinegar foams white Nitric acid turns black
FLAME TEST Melts faster than steel Slivers will flare up white and green Melts at 800° F, aluminum and magnesium 1200° F
MAGNETIC Non-magnetic Non-magnetic Non-magnetic
R&M ALLOY RM 3060 RM 3018 RM 3016
CAST IRONS AND MANGANESE
TEST/METAL GREY CAST MALLEABLE AND DUCTILE CAST MANGANESE STEEL 12%
USES Motors, engine blocks and heads, gearbox housings, machine frames Pipe fittings, yokes, shifting forks Hammermill and crusher parts, track parts subject to impact wear
FRACTURES Dark grey Dark grey Coarse grained
SURFACE UNFINISHED Dull grey – evidence of sand mold Dull grey Coarse grained – evidence of sand mold
SURFACE MACHINED Fairly smooth light grey Smooth light grey Not machined typically
MAGNETIC Yes Yes Not unless work hardened
FILE TEST Files easily Files easily Maybe too hard to file
CHISEL TEST Small powdery chip Small chips Very hard to chisel
R&M ALLOY SURE CAST 935-2 SURE CAST 935-2 HF 540

Mind over Metals