A tube matrix, comprising: a metal plate having a first surface, and an opposite second surface and a plurality of holes that extend from said first surface to said second surface, a plurality of hydrogen permeable metal tube elements, wherein each tube element from said plurality of hydrogen permeable tube elements has a first end, an opposite second end and a flare structure proximate said first end, wherein said plurality of hydrogen permeable metal tube elements extend through said plurality of holes in said plate, wherein each said tube element in said plurality of hydrogen permeable tube elements is an assembly comprising a palladium alloy tube and a welding termination attached to said palladium alloy tube, wherein said flare structure is part of said welding termination, and said flare structure prevents the tube elements from passing completely through the holes; and wherein said plate and said welding termination are made from the same metal alloy, characterized in that each hole from said plurality of holes has a first beveled surface with a first angle and a first depth that funnels into said hole from said first surface, and said flare structure has a second beveled surface with a second angle and a second depth that matches the first angle and the first depth of the first beveled surface, whereby the flare structure seats flush against the first beveled surface with none of the flare structure extending above the hole, and said second beveled surface of each said tube element is welded to said first beveled surface of each said hole through which each said tube element passes. a metal plate having a first surface, and an opposite second surface and a plurality of holes that extend from said first surface to said second surface, a plurality of hydrogen permeable metal tube elements, wherein each tube element from said plurality of hydrogen permeable tube elements has a first end, an opposite second end and a flare structure proximate said first end, wherein said plurality of hydrogen permeable metal tube elements extend through said plurality of holes in said plate, wherein each said tube element in said plurality of hydrogen permeable tube elements is an assembly comprising a palladium alloy tube and a welding termination attached to said palladium alloy tube, wherein said flare structure is part of said welding termination, and said flare structure prevents the tube elements from passing completely through the holes; and wherein said plate and said welding termination are made from the same metal alloy, characterized in that each hole from said plurality of holes has a first beveled surface with a first angle and a first depth that funnels into said hole from said first surface, and said flare structure has a second beveled surface with a second angle and a second depth that matches the first angle and the first depth of the first beveled surface, whereby the flare structure seats flush against the first beveled surface with none of the flare structure extending above the hole, and said second beveled surface of each said tube element is welded to said first beveled surface of each said hole through which each said tube element passes.