| 摘要 |
<p>This invention provides metal-thermoplastic-metal laminates and a process for preparing same which possess critical service properties of low coefficient of linear thermal expansion, low inelastic ratio, and excellent flexural stiffness. The laminate is comprised of a thermoplastic core layer having a minimum thickness of 0.0483 cm; and a metal layer laminated on each side of the core, each metal layer having a minimum thickness of 0.00127 cm. When the core is high density polyethylene, aluminum is not the metal layer on both sides; and when the core is polypropylene, aluminum is the metal layer on each side. The laminate has a maximum weight of about 5.37 kg/m2 and the thickness ratio of the sum of the metal layer thicknesses to the core layer thickness is described by the region of numerical overlap of the parameter TR(YSm/TSc) wherein TR is the thickness ratio of the sum of the metal layer thicknesses to the core layer thickness; YSm is the thickness-weight-average tensile yield strength of the two metal layers at an offset of 5% elongation; and TSc is the tensile strength of the core layer; as determined from the areas defined by the relationships of TR(YSm/TSc) to the inelastic ratio of the laminate as measured in flexure at 5% strain in the outer metal layers at the point of maximum deflection (IR?); and the coefficient of linear thermal expansion of the laminate (CLTE?); the lower boundary of these areas being defined by the equation of a straight line y = mx + b in which y is the y-axis parameters of IR? and CLTE? , x is the x-axis parameter of TR(YSm/TSc), m is the slope of the straight line and b is the intercept on the y-axis. The laminates are useful in construction applications such as outer and inner building panels, appliance panels, and transportation vehicle body panels, for example, automobiles, boats and airplanes.</p> |
