Shape Memory Alloy Rock Splitters (SMARS)

mechanical and fluid systems
Shape Memory Alloy Rock Splitters (SMARS) (LEW-TOPS-122)
Provides a compact, powerful, non-explosive method for fracturing rocklike materials
NASA's Glenn Research Center have developed a groundbreaking method for using shape memory alloys (SMAs) to split apart rock formations without explosives or hydraulics. Conventional approaches present difficulties in transportation and operation and can badly damage underlying samples during use. Glenns innovation exploits cutting-edge SMA compositions to deliver controllable stresses in excess of 1500 megapascals (MPa), which is up to four times greater than the force exerted by commercial equiatomic SMAs. The SMA compositions are also tunable to multiple activation temperatures up to 400°C, depending on the usage environments. Glenns Shape Memory Alloy Rock Splitters (SMARS) device generates this power without any demolition damage to the surrounding environment, and in a package that combines reliability, ease of setup and activation, and cost-effectiveness. This technology could prove invaluable to enterprises as varied as oil drilling, mining, civil engineering, fossil collection, and search-and-rescue operations - any field that requires compact, but large, static forces.

The Technology
Glenn's revolutionary SMARS device is fabricated from nickel-titanium-halfnium (NiTiHf), nickel-titanium-zirconium compositions, or a combination. These compositions contain a secondary, nanometer-sized precipitate phase, which is produced through processes of compositional control and ageing heat treatments. Glenn's novel materials and processes have yielded a SMA composition that produces much higher stresses than other SMAs on the commercial market. The SMARS device is composed of 1) SMA material as the actuating member; 2) a casing heater placed around the SMA member; 3) a DC or AC power source to provide current through the heater; 4) pointed tips for acute penetration into rock formations; and 5) a hand-press to reset the SMA element after each use. In the rock-splitting process, a hole equal to the diameter of the SMA element is drilled in the portion of the rock where the fracture is desired. Next, the pre-compressed SMA is inserted into the hole, and AC or DC current is applied to energize the devices heaters. Once the heater achieves the critical transformation temperature, the SMA will begin to expand within seconds. Since its expansion is constrained by the rock walls, the SMA will eventually exert up to 1500 MPa of stress, splitting the rock apart. When the current is removed and the heater cools, the SMA material returns to its pre-compressed state. At this point, the material can be recovered, so the process is repeatable after reshaping. The SMA actuating members were also designed to achieve displacement greater than the materials strain output. Glenns SMARS device provides high-powered rock fracturing that is controllable, reliable, and comparatively simple without the use of explosives, hydraulics, or chemicals.
Glenn's SMARS device is ideally suited to break up rock formations as part of oil and gas drilling projects
  • Powerful: Produces stresses that are four to five times more powerful than commercial equiatomic nickel-titanium (NiTi) alloys generate
  • Controllable: Causes no demolition or vibration damage to the surrounding environment or other nearby projects
  • Convenient: Needs little setup and activation compared to other static methods, such as chemical agents, which can take days to react
  • Simple and safe: Requires only heat input to activate no complex valve systems or hydraulic fluids are needed
  • Compact: Has small volume and extremely low weight, so it can be transported more easily than heavy hydraulic wedges, explosive materials, or chemicals
  • Versatile: Features portability and setup advantages that allow it to be used in spaces that heavy equipment cannot access
  • Reusable: Reverts to original deformation when cooled, and can be reshaped so the SMA material can be recovered and reused

  • Hydraulic fracturing (including use as a proppant)
  • Mining (gemstone, precious metal mining)
  • Archaeology
  • Search and rescue
  • Oil and gas
  • Commercial space
Technology Details

mechanical and fluid systems

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