Hardwire®

What is Hardwire® Tape?

Hardwire® is a family of reinforcements made from ultra high strength twisted steel wires. It is a revolutionary material that affords end users the ability to put ultra high tensile strength steel (11 times stronger than typical steel plate) inside or outside just about any material. Simply worded, Hardwire® is moldable steel. Hardwire® can be molded into thermo-set, thermoplastics or cementitious resin systems with never before seen ease and it occupies a new reinforcement niche between fibers and steel rebar. This creates a new class of reinforcements, micro-rebar, that will work with composite, plastic, and cement based processes. Further, Hardwire® can be used to upgrade steel, wood, or concrete structures in both new construction and in retrofit applications.

Composites made from Hardwire® are up to 70% thinner and 25% lighter than composites made with glass fibers. When it comes to cost Hardwire® is in a class by itself. Hardwire® is priced like glass, yet performs like carbon at a fraction of the cost. Hardwire®® was literally born on the shop floor making it ideal for all types of molding operations, where ease of production has been designed in from the start. Because Hardwire® can be molded with just about any resin you can then hybridize it with all existing commercial fibers.

Hardwire® will open the doors to new material combinations and processes. Hardwire® has been used to reinforce wood products using common wood adhesives, it has been used to reinforce thermo-set resins, saving weight, thickness, labor and eliminating costly quality problems like porosity, ply wrinkling and exotherms, and it has been laminated into thermoplastics that were simply too viscous to be reinforced with other fibers. Using Hardwire®, boat builders can become ship builders, thermoplastic molders can make steel reinforced polypropylene and retrofit companies can now reinforce steel with even better steel instead of lesser materials.

Hardwire® is also one of the world’s toughest and most blast resistant materials. Explosion tests performed by the United States Navy have proven that Hardwire® reinforced urethane and polyureas can upgrade steel structures to provide significant blast protection.

  • Cutting Edge Family of Strengthening Reinforcements
  • Increases Structural Capacity
  • Provides Versatile Fortification Systems
  • Offers Blast Protection Armor Qualities
  • Enhancements for New Construction and Retrofit Solutions
  • Provides Protection and Architectural Solutions

Hardwire® is available as single end rovings, or as unidirectional tapes. Hardwire® cords come in three primary structures. Hardwire® uni-directional tapes can be specified with wire cord counts from 4 to 20 wires per inch resulting in strengths ranging from 1.1 to 8 kips per inch. Hardwire® uni-tapes are available in widths of 12” and lengths up to 2000 ft. Six miles of Hardwire® tape can be produced every eight hours. All Hardwire® material is shipped on spools that make Handling the material on the shop floor a breeze.

Hardwire® Composite Reinforcements are used in a variety of applications from flooring reinforcement, historical building restorations and retrofits, laminates in the boating industry and to strengthening bridges and buildings.

Cord Types

Hardwire® reinforcements are all based on twisted wire cords. Why??? Because Hardwire® works to blend somewhat contrary characteristics together to make an engineering material that combines the ultimate quality, strength, stiffness, handle-ability, and bond with the resin systems that make up Hardwire® reinforced composites, plastics and cements.

To make the highest strength wire possible, ultimate quality steel must be drawn down to very fine wire diameters. It is only at ultra fine diameters that steel can be transformed in to the ultimate steel microstructure of pearlite. Further, when the wire is drawn down, the grains, or single crystals of steel, contained in the pearlite micro structure are oriented in the wire drawing direction, further increasing the directional strength of the wire while balancing the off axis properties so critical to toughness and fatigue. The process used to draw the fine wires is so brutal that only the highest quality steel can survive to become Hardwire®.

Individual filaments are then twisted together into cords where the specific twist angle is precisely controlled. Anywhere from 2 individual wires to 50 wires are twisted together during this step. Last, for some products, a wrap wire is added to the twisted bundle to add specific characteristics for Handling or bonding to highly viscous resins. The twisted wire cords are basically bundles of the ultra tensile wires….pre packaged, to handle and have flexibility like small wires (and the insane strength of 450KSI), but also have the economic Handling benefits of a larger wire size. The cords are varied between those highly twisted cords for optimum tensile strain to allow for better ductility, slightly twisted cords which are more open to allow resin penetration, yet still maintain cable like properties and straight cords with a twisted over warp to provide balanced tensile and compressive behavior.

The Cord

The 3x2 Hardwire® is a high carbon steel cord with a micro-fine brass or galvanized coating. The 3X2 cord is made by twisting 5 individual wire filaments together - 3 straight filaments wrapped by 2 filaments at a high twist angle. The result is an easy to handle cord that combines great engineering values with excellent economics. If your application is tension dominated choose the 3x2.

Description
Filament Diameters (in)
Cord Diameters (in)
Break (n)
Break (lbs)
Break (kips)
Elongation (Strain To Failure)
3X2
.0138
.035
1540
346.2
.3462
2.1%
3X2-G
.0146
.037
1580
355
.3550
2.1%

Characteristics:

  • Excellent mix of engineering properties - Up to 8 KIPS/inch.
  • Great stiffness, instant wet-ability, and excellent conformability.
  • Works in all resins.
  • Asymmetric shape acts like a screw and gives great mechanical bonding characteristics.
  • Excellent fatigue properties in tension and in high-flex situations.
  • Great choice for extrusion and pultrusion applications

3X2 Tape

Hardwire tapes are constructed from the 3X2 cord type and is available in standard brass or galvanized. These tapes are 12” wide (12” of steel fiber, 12 ½” grid) and are sold in 50’, 500’ and 2000’ rolls. Fiber density is measured by the number of steel cords per inch. All Hardwire tapes come in low, medium, and high densities.

Cold Drawn Steel

Cold Drawn Steel Tire cord is the strongest metallic reinforcement made. The micro-hardness of the steel filament is similar to that of a quenched steel (Fig. 1). This indicates that cold drawn tire cord filament has strength similar to or higher than quenched swords, knifes and other products with martensitic microstructure resulting in the highest strength achieved in steels by heat treatment. Such a high strength in a cold drawn tire cord filament is due to nano-size of phases present in steel microstructure.

Before drawing, two phases, namely, ferrite, an iron rich ductile phase, and cementite, an intermetallic compound with a high strength (Fig. 2), are present in a form of colonies of plates, so called pearlite (Fig. 3). Thickness of these ferrite and cementite plates randomly orientated with respect to the wire axis is around 60 nm and 10 nm, respectively.

During drawing, ferrite and cementite plates become orientated along the wire axis, and their thickness becomes less than 10 nm and 2 nm, respectively (Fig. 4) showing atomic structure of a drawn steel filament. Such a small thickness of ferrite and cementite plates result in a record high strength of steel filaments. Processing stages of steel cord manufacturing include rough drawing, patenting, brass plating, fine drawing and cabling. In rough drawing, steel rod diameter is reduced from 5.5 mm to around 1.5 mm. Patenting is a special heat treatment used to restore steel ductility before fine drawing during which diameter is further reduced to about 0.2 mm. This deformation is very high resulting in a length increase of a 10 m long wire segment to almost 1 km long filament.