One aspect of the disclosure provides an iron-based hardfacing layer which includes hard or wear resistant phases resulting at least in part from dissolution of silicon and/or boron carbide particles into a liquid iron-based metal during the fabrication process. In an embodiment, the hardfacing layer is formed by a fusion welding process in which carbide particles are added to the molten weld pool. In an example, the filler metal supplied to the welding process is a mild steel. In an embodiment, the hardness as measured at the surface of the hardfacing ranges from 40 to 65 HRC. In an example, the iron-based hardfacing layer also includes tungsten carbide particles.

One aspect of the disclosure provides an iron-based hardfacing layer which includes hard or wear resistant phases resulting at least in part from dissolution of silicon and/or boron carbide particles into a liquid iron-based metal during the fabrication process. In an embodiment, the hardfacing layer is formed by a fusion welding process in which carbide particles are added to the molten weld pool. In an example, the filler metal supplied to the welding process is a mild steel. In an embodiment, the hardness as measured at the surface of the hardfacing ranges from 40 to 65 HRC. In an example, the iron-based hardfacing layer also includes tungsten carbide particles.

Method for producing a composite structure comprising the direct bonding of at least one first wafer with a second wafer, and comprising a step of initiating the propagation of a bonding wave, where the bonding interface between the first and second wafers after the propagation of the bonding wave has a bonding energy of less than or equal to 0.7 J/m.sup.2. The step of initiating the propagation of the bonding wave is performed under one or more of the following conditions: placement of the wafers in an environment at a pressure of less than 20 mbar and/or application to one of the two wafers of a mechanical pressure of between 0.1 MPa and 33.3 MPa. The method further comprises, after the step of initiating the propagation of a bonding wave, a step of determining the level of stress induced during bonding of the two wafers, the level of stress being determined on the basis of a stress parameter Ct calculated using the formula Ct=Rc/Ep, where: Rc corresponds to the radius of curvature (in km) of the two-wafer assembly and Ep corresponds to the thickness (in m) of the two-wafer assembly. The method further comprises a step of validating the bonding when the level of stress Ct determined is greater than or equal to 0.07.