Ngk Spark Plug Company, Limited

Hitachi Metals, Ltd.

Tomo-o Tanaka

Osamu Yoshimoto

Tsutomu Shibata

Takehito Kuno

Takaaki Kikai

Toshihiro Uehara

Makoto Kuribayashi

Tomonori Kanemaru

Norihide Kachikawa

Yoshiaki Sato

Tomoki Murata

Takahiro Masumoto

An electrochemical reaction unit which includes a unit cell including an electrolyte layer, a cathode, and an anode facing each other in a first direction; a current collector disposed on a cathode side of the unit cell; and an electrically conductive porous bonding layer. A bonding region contains a block portion and an electrical conductivity securing portion. The block portion has a pore having a diameter that is 20% or more than the thickness of the bonding region in the first direction. The block portion extends inward from one of opposite ends in a second direction orthogonal to the first direction of the bonding region, and reaches and contains the pore satisfying the pore requirement. The electrical conductivity securing portion is located toward the other end of the bonding region and has a smaller average diameter of pores than the block portion.

Electrochemical reaction unit and fuel cell stack

An electrode material for at least one of a center electrode () and a ground electrode () provided with a chip () for use in a spark plug (). The electrode material contains Ni as a principal component, and has a Si content of from 0.50% to 1.0% by mass, an Al content of from 0.2% to 2.0% by mass, a Cr content of from 12% to 34% by mass, a rare-earth element or the like content of from 0.03% to 0.2% by mass, a Fe content of more than 0% but not more than 20% by mass, a C content of not more than 0.10% by mass, and a Mn content of not more than 1.0% by mass. The total content of Si and Al is not less than 0.80% by mass, and less than one tenth of the Cr content.

Electrode material and spark plug

A spark plug () includes a metallic shell () and a ground electrode () resistance-welded to the metallic shell (). The ground electrode () is formed from a metal material in which precipitates PR containing at least one of an oxide, an intermetallic compound, etc., are precipitated in grain boundaries. The diameter of an equivalent circle of a precipitate PR having the greatest area is 50 &#x3bc;m or less, and the shortest distance between the precipitates PR is 2 &#x3bc;m or greater. The area occupied by the precipitates PR on the section of the heat-affected zoneA is equal to 65% or more the area occupied by the precipitates PR (the diameter of an equivalent circle of a precipitate PR having the greatest area) on a section of the normal zoneB.

Spark plug

A spark plug includes at least one of a center electrode or a ground electrode that is produced by the steps of: mixing a matrix metal with carbon so that the carbon content of the resultant mixture is adjusted to 80 vol. % or less; subjecting the mixture to powder compacting or sintering, to thereby form a core; placing the core in a cup formed of nickel or a metal containing nickel as a main component; and subjecting the cup to cold working. The thus-produced electrode exhibits favorable thermal conductivity and good heat dissipation, by virtue of the small difference in thermal expansion coefficient between the core and an outer shell. The spark plug including the above electrode exhibits excellent durability.

Spark plug electrode, method for producing same, spark plug, and method for producing spark plug

A spark plug is provided having at least one of a center electrode or a ground electrode. The electrode comprises: a core formed of a composite material containing a matrix metal, the matrix metal being copper or a metal containing copper as a main component, and carbon dispersed in the matrix metal in an amount of 10 to 80 vol. %, the carbon having a thermal conductivity higher than that of the matrix metal. The electrode also contains an outer shell which surrounds the core and which is formed of nickel or a metal containing nickel as a main component. The thus-produced electrode exhibits favorable thermal conductivity and good heat dissipation, by virtue of the small difference in thermal expansion coefficient between the core and an outer shell. The spark plug including the above electrode exhibits excellent durability.

A spark plug which exhibits improved resistance to high-temperature oxidation of an electrode, and improved resistance to spark-induced erosion of, improved resistance to oxidation of, and improved joining reliability of a tip joined to the electrode. A spark plug has spark members; each of the spark members has a weight of 1.5 mg or more; and a center electrode and a ground electrode contain Ni as a main component, C in an amount of 0.005% by mass to 0.10% by mass, Si in an amount of 1.05% by mass to 3.0% by mass, Mn in an amount of 2.0% by mass or less, Cr in an amount of 20% by mass to 32% by mass, and Fe in an amount of 6% by mass to 16% by mass.

Growing community of inventors

Kitanagoya, Japan

Tomo-o Tanaka