heat conducting metal

Best Metals for Conducting Heat

Thermal conductivity is the term that describes how quickly a material absorbs heat from areas of high temperature and moves it toward areas of lower temperature. The best heat-conducting metals have high thermal conductivity and are useful for many applications, such as cookware, heat exchangers, and heat sinks. On the other hand, metals with a lower rate of heat transfer are also useful where they can act as a heat shield in applications that generate large amounts of heat, such as airplane engines.

Here’s a ranking of heat conducting metals and metal alloys from lowest to highest average thermal conductivity, in Watts/meter-K at room temperature:

  1. Stainless Steel (16)
  2. Lead (35)
  3. Carbon steel (51)
  4. Wrought iron (59)
  5. Iron (73)
  6. Aluminum Bronze (76)
  7. Copper brass (111)
  8. Aluminum (237)
  9. Copper (401)
  10. Silver (429)

Stainless Steel

With one of the lowest thermal conductivities for a metal alloy, stainless takes much longer to conduct heat away from a source than, say, copper. This means that a pot made of stainless would take much longer to heat up food than a copper-bottom pot (though stainless has other benefits). Steam and gas turbines in power plants use stainless steel because of its heat resistance, among other properties. In architecture, stainless steel cladding can resist high temperatures longer, keeping buildings cooler in sunlight.

Aluminum

While aluminum has a slightly lower thermal conductivity than copper, it is lighter in weight, cheaper, and easier to work with, making it a better choice for many applications. For example, microelectronics such as LEDs and laser diodes use tiny heat sinks with aluminum fins that project into the air. Heat generated by the electronics transfers from the chip to the aluminum and then to the air, either passively or with the help of forced airflow convection or a thermoelectric cooler.

Copper

Copper has a very high thermal conductivity and is much cheaper and more available than silver, which is the best metal of all for conducting heat. Copper is corrosion resistant and resists biofouling, which makes it a good material for solar water heaters, gas water heaters, and industrial heat exchangers, refrigerators, air conditioners, and heat pumps.

Other factors affecting heat conduction

When considering the best metals for heat conduction, you must also take into account other factors in addition to thermal conductivity, which affect the rate of heat flow. For example, the initial temperature of the metal can make a huge difference to its heat transfer rate. At room temperature, iron has a thermal conductivity of 73, but at 1832°F, its conductivity drops to 35. Other influences include the temperature difference across the metal, the thickness of the metal, and the surface area of the metal.

For the largest selection of metals in the Southwest, contact Industrial Metal Supply.

Data taken from Engineering Toolbox.


Know Your Metalworking Safety Gear

Whether you’re welding, cutting, shaping, finishing, or grinding metal, you need to protect yourself from sharp edges and metal dust that can injure eyes, hands, skin, lungs, and more. Selecting the proper safety wear is an important part of any metalworking job.

Eye and lung protection

The primary article of safety gear for any metal shop worker should be safety glasses or goggles. Glasses are available with lightweight, flexible frames with impact resistant lenses and come in a range of styles and lens colors, including clear, smoke, yellow, blue, and mirrored. Goggles are heavier but provide additional side and top protection, especially from gases and air-borne particles.

Respirators provide protection from dangerous gases, vapors and particulate hazards produced when fillers, coatings, shielding gases, and metals are heated to high temperatures during the welding process. Ergonomically designed respirators made of silicone are available that fit comfortably with or underneath goggles or a welding helmet.

Safety gloves

There are dozens of styles of safety gloves on the market, for many types and levels of protection. It’s important to balance the protection level with the dexterity required in working with safety gloves. For example, a leather glove provides strong protection against cuts, yet can be clumsy, making it hard to grasp and hold small objects. At the same time, painting or staining metal or wood with harsh chemicals may best be accomplished with waterproof, flexible latex gloves.

High-tech nitrile yarn gloves provide high-level cut resistance, and double dipped coating adds chemical resistance while retaining flexibility. Contour fit synthetic leather and neoprene welding gloves provide sensitivity in the fingers, as well as strong protection on the knuckles and other areas.


Choosing the right size glove is just as important as choosing the right style. For example, if a worker with small hands uses a pair of XXL gloves, they may easily slip down or off right when their protection is needed. Conversely, a person with very large hands can’t squeeze into medium-sized gloves, and so may not wear the necessary protection.

Knee, Back & Arm Protection

Kneeling or crouching while welding a difficult part together may cause knee strain or injury. Protect your knees with a set of kneepads with either foam padding or gel inserts. Styles are available for those who are allergic to latex. Kneepads with a two-strap system are more comfortable and are easy to put on and take off.
 
Welding jackets, capes, and sleeves made of flame resistant materials add additional protection for backs and arms during the welding process.

For more information on metalworking safety gear, visit Industrial Metal Supply.


Before Your First Weld: How to Prepare

The first step in welding preparation is deciding which method of welding to use. This will depend on the skill level of the welder and the equipment available. If welding outdoors, you will need to consider the weather – it’s not a good idea to perform MIG or TIG welding in windy conditions, which could blow away the protective gases that shield the weld from oxidation.

Before firing up a welding torch, it’s important to be fully prepared with all the necessary welding materials and equipment, along with the metal pieces to be welded.

Preparing metal for welding should include inspection and removal of any rust or paint using steel wool or a grinder with a wire brush. You also may need to remove an old or bad weld with a grinder. Some types of welding can be accomplished even with rusty or dirty metal parts, or on painted metal. However, without cleaning off contaminants such as coatings, dust or debris from the metal surface, the final weld may be weak or defective.

Welding materials

Materials for welding include not only the welding machines themselves, but all sorts of equipment and supplies. Consumables include welding wire, solder, brazing rods, flux, anti-spatter, and stick electrodes. You will need MIG wire contact tips for the welding torch, and replacement gas nozzles and diffusers. Soapstone can be used to visibly mark the desired welding path so that it can be seen even through a darkened face shield. Various metal weld-on tabs may be necessary to create handles, holes, or flanges welded onto pipes or other objects.

To protect skin from sparks you will need to wear personal protective equipment, including leather welding bibs, overalls or aprons, leather gloves, long-sleeved shirts, long pants, and leather shoes. An auto-darkening welding helmet allows the welder to see as clearly as possible without eye damage, even in the strong light of the welding flame. Fiberglass welding blankets can also be used to prevent the spread of sparks.

You may need a variety of welding magnets for holding the metal pieces in different configurations or for welding thin pieces of sheet metal. Projects of various sizes and shapes require different types of magnets, including squares with various angles options, Adjust-O magnets that turn on and off, sheet metal magnets, corner magnets, and snake magnets. Clamps, adjustable welding tables and workstands can also help hold parts in the necessary position.

Contact IMS for all the necessary welding materials for your project.