Samsung Electronics Co., Ltd.

Posco

Posco Co., Ltd

Jae-Hong Shim

Sang Jin Lee

Do-young Kam

Hyung Gu Kang

Gyu Jin Jo

Dong Chul Chae

Hyung-suck Cho

Hyung-Gu Kang

Yong-Heon Lee

Jong-Jin Jeon

An austenitic stainless steel having excellent processability and surface characteristics and a method of manufacturing the austenitic stainless steel are disclosed. The austenitic stainless steel includes, by weight %, 0.005% to 0.15% of carbon (C), 0.1% to 1.0% of silicon (Si), 0.1% to 2.0% of manganese (Mn), 6.0% to 10.5% of nickel (Ni), 16% to 20% of chromium (Cr), 0.005% to 0.2% of nitrogen (N), the remainder iron (Fe) and other unavoidable impurities, wherein a degree of Ni surface negative segregation defined by the following Formula (1) is in a range of 0.6 to 0.9.(C)/(C)&#x2003;&#x2003;Formula (1),

Austenitic stainless steel having excellent processability and surface characteristics, and manufacturing method therefor

An austenitic stainless steel product having excellent surface characteristics and a manufacturing method therefor are disclosed. The disclosed austenitic stainless steel product comprises an austenitic stainless steel comprising, by weight percent, 0.005 to 0.15% of C, 0.1 to 1.0% of Si, 0.1 to 2.0% of Mn, 6.0 to 8.0% of Ni, 16 to 18% of Cr, 0.1 to 4.0% of Cu, 0.005 to 0.2% of N, 0.01 to 0.2% of Mo, and the remainder comprising iron (Fe) and other unavoidable impurities, and a Ni surface negative segregation thereof defined by the following formula (1) is 0.6 to 0.9 and the martensite fraction thereof is 10 to 30%.(C)/(C)&#x2003;&#x2003;formula (1) Here, Cis the minimum concentration of Ni on the surface and Cis the average concentration of Ni on the surface.

Austenitic stainless steel product having excellent surface properties and manufacturing method of the same

A probe apparatus for the electrical inspection of a printed circuit board (PCB) assembly includes a probe assembly for inspecting the electrical circuitry of a PCB having electronic components mounted thereon. A first driving mechanism is provided for moving the probe assembly rectilinearly, and a guide is provided for guiding the rectilinear movement of the probe assembly. The probe assembly includes a probe tip for making contact with a solder joint on the PCB to detect a signal for the electrical inspection, a force sensor combined with the rear portion of the probe tip for measuring a contact force applied to the probe tip when the probe tip makes contact with the solder joint, a location sensor for measuring the location of the probe tip when in contact with the solder joint, and a device for controlling the location of the probe tip, according to the measured contact force and location thereof. The probe may further include a second driving mechanism for controlling the angle of inclination of the probe assembly to solder joints. Such a probe is improved in adaptability to the various patterns of the solder joints and thus enables stable testing of the PCB, by preventing poor soldering as well as vibration of the probe tips.

Probe apparatus for electrical inspection of printed circuit board

Growing community of inventors

Seoul, South Korea

Jae-Hong Shim