Heat-resistant electronic systems and circuit boards

A method of making a heat-resistant equipment comprising:

• providing an equipment having a frame;
• providing an electronic circuit board rigidly mounted with a significant mounting stress applied onto, and at a designated contacting region on, said frame;
• said circuit board having a plurality of electronic circuit components fusion-bonded thereon;
• said circuit board consisting essentially of a ceramic or plastic board with a top major surface having a plurality of designated bonding regions for fusion-bonding said plurality of electronic circuit components;
• and
• supplying a fusible metal-matrix bonding composite, which comprises a composite matrix and a plurality of refractory reinforcing elements substantially uniformly and stably dispersed therein, for fusion-bonding said plurality of circuit components;
• said mounting frame, circuit board, and fusible metal-matrix composite at least comprising materials which, from one another, differ significantly in coefficients of thermal expansion to thereby produce significant thermal mismatch stresses at said bonding or contacting regions;
• said substantially uniformly and stably dispersed, refractory reinforcing elements in the bonding composite providing heat resistance to the bonding regions between the circuit components and the circuit board and, despite a combined presence of said mounting stress and said thermal mismatch stress at said various bonded or mounted regions, making the equipment frame, the circuit board, and the circuit components heat-resistant.

A heat-resistant article of manufacture comprising:

• a first body of a first solid material having a first exposed surface thereon;
• a second body of a second solid material having a second exposed surface thereon;
• at least one part of said first exposed surface being in close proximity with said second exposed surface to thereby form a contact region therebetween;
• and
• a heat-resistant composite at said contact region to bond the at least one part of said first exposed surface to said second exposed surface at said contact region;
• said composite comprising a composite matrix and a plurality of substantially non-segregating solid reinforcing elements substantially uniformly dispersed therein.

A heat-resistant equipment comprising:

• an equipment having a mounting frame and an electronic circuit board rigidly mounted, with a significant mounting stress, at a designated contacting region on the frame;
• said circuit board consisting essentially of a ceramic or plastic board with a top major surface which has a plurality of designated bonding regions for locating thereat a plurality of electronic circuit components;
• and
• a fusible metal-matrix bonding composite comprising a composite matrix and a plurality of solid refractory reinforcing elements substantially uniformly and stably dispersed therein;
• said bonding composite fusion-bonding said plurality of circuit components onto the top major surface of said circuit board at said designated bonding regions;
• said mounting frame, circuit board, and bonding composite having materials which, among one another, differ significantly in coefficients of thermal expansion to thereby introduce a significant thermal mismatch stress at said bonding or contacting regions;
• said substantially uniformly and stably dispersed, solid refractory reinforcing elements in the bonding composite providing heat resistance to the bonding regions between the circuit components and the circuit board and, despite a combined presence of said mounting stress and said thermal mismatch stresses at said various bonding or contacting regions, making said equipment in its entity including the mounting frame, the circuit board, and the circuit components heat-resistant.

A method of making substantially non-segregating solid reinforcing elements for suspension in a liquid bonding composite matrix of a preselected liquid density dm for use in a heat-resistant equipment, said equipment containing a plurality of electronic circuit components mounted or bonded on an electronic circuit board on said equipment, comprising:

• supplying for each of a plurality of said solid reinforcing elements a respective solid inner core material of a selected shape and having a preselected average volume v1, a preselected average density d1 and a preselected average weight w1;
• providing on each of said respective inner core material a respective solid outer shell material having a preselected average volume v2, a preselected average density d2 and a preselected average weight w2;
• and
• adjusting the values of v2 and v1, so that each of said reinforcing elements has an average weight of v1d1+v2 d2 which is substantially equal in weight to that of a volume v1+v2 of said liquid bonding composite matrix having said preselected liquid density dm to thereby achieve a substantially non-segregating quality of said solid reinforcing elements when suspended in said liquid bonding composite matrix, thereby forming a solid-reinforced bonding composite containing said plurality of reinforcing elements substantially uniformly distributed in said composite matrix in a liquid suspension form.

A method of making a heat-resistant metal-matrix composite comprising:

• supplying a matrix of a metal or an alloy thereof;
• providing a plurality of substantially non-segregating, solid reinforcing elements;
• and
• stably dispersing the plurality of said solid reinforcing elements substantially uniformly in said metal matrix to form a metal-matrix composite;
• said non-segregating reinforcing elements consisting essentially of a material significantly more heat-resistant than said composite matrix to thereby make the resultant metal-matrix composite also heat-resistant.