Despite the reports of shortages over the past several years, there are still tons of the metal around.
Multitasking again? Watching your new, huge, flat-screen monitor; reading this piece on your tablet; and, calling in a pizza on your smartphone? The chances are that each screen you’re looking at, and tapping on, will contain some indium—albeit in tiny quantities. That’s because indium (when alloyed with tin) is the “go to” metal for LCD and touch screens.
In fact, according to the latest figures from the likes of Indium Corp. and AIM Specialty Materials, demand for the metal in flat panel displays (FPDs) alone ranges from around 52 percent (AIM) to 56 percent (Indium Corp.) of total net demand for the metal.
Forecast Net Demand for Indium: 2013
Source: Indium Corporation
Indium’s uses other than in FPDs include:
- Solders: Indium is an important element in lead-free solders. In addition to improving the solders’ resistance to thermal fatigue and lowering their tendency to crack, indium has replaced the lead once found in many solders that have been banned in many countries.
- PVs: In photovoltaics (PVs), indium is used, together with copper, gallium and selenium in the manufacture of CIGS (and, without the gallium, CIS) thin film solar cells.
- Thermal Interface Materials: Not least because of its excellent thermal conductivity, indium acts as an effective and efficient interface between electronic components and the heat sinks employed to cool them down.
- Batteries: In certain types of batteries—e.g., alkali and zinc air—indium compounds are used to improve performance and efficiency.
- Alloys/Compounds: Because of its low melting point, alloys containing indium can be used to hold high-value items while they are being worked on; e.g., glass lenses while they are being ground, or turbine blades. The alloy can then be melted away at a low temperature with no resulting damage to the item it held. And in nuclear reactors, there are four general methods of controlling either the power or the flux of neutrons. Indium is an excellent neutron absorber. Alloyed with silver and cadmium (silver: 80 percent, indium: 15 percent and cadmium: 5 percent), the resulting material is enclosed in stainless steel tubes and serves as an effective poison, particularly in pressurized water reactors.
- Compound Semiconductors & LEDs: Indium is used in tiny quantities in both LEDs (usually those producing light in the longer wavelengths of the visible spectrum) and in compound semiconductors (where its main use is in optoelectronics—both in photodetectors and transmission lasers).