temperature transformation diagram): 온도, 시간, 변태곡선
3) 표면 경화법
① 화학적 표면 경화법
ⅰ) 침탄법: 고체(목탄, 코우크스), 가스(CO,CO2,메탄,에탄,프로판), 침탄깊이 0.5~2mm
ⅱ) 시안화법: KCN, NaCN (청화법)
ⅲ) 질화법: NH3, 50~100 Hr, 자동차의 크랭크축, 캠, 펌프축 등에 사용. 질화층 0.4~0.8mm
* 특징
이러한 관점에서 Pb Solder는 Pb의 매장량이 높고, 결착성이 좋으며 가장 좋은 특성으로는 낮은 융점 때문에 Pb Solder의 사용이 널리 퍼져 있었다. 사실 접합부에 Pb를 사용하는 것은 전도도가 좋기 때문은 아니다. Pb의 전도도는 Cu의 7%밖에 되지 않는다. 그러나 Pb를 사용하게 된 이유는 역시 대량 생산제품의
1. 제조방법
1) Styrene과 Acrylonitrile의 Copolymerization
라디칼 중합에 의한 공중합 반응에 있어서, 생성되는 공중합체의 조성은 각 단량체의 조성은 각 단량체의 조성은 각 단량체의 상대적 반응성과 농도에 의해서 조절된다.
어떤 한 단계에서 생성된 공중합체 중의 단량체 M의 몰분율을 F₁그 단
High-temperature decomposition
High-temperature splitting of water occurs at about 3000 °C. At this temperature, 10% of the water is decomposed and the remaining 90% can be recycled. To reduce the temperature, other processes for hightemperature splitting of water have been suggested:
▸Thermo-chemical cycles.
▸Hybrid systems coupling thermal decomposition and electrolytic
medium을 통해 처리하여 식품의 형태적 변형과 손상을 주지 않고 식품 저장성과 안정성을 높게함
② 원치 않는 병원성 미생물과 bio process작용, enzyme을 저해하여 식품의 질 향상
1. Pressure vessel(chamber) + its closure
2. Pressure generation system (pump)
3. Temperature control device
4. Fluid handling system
hightemperatures. For safety reasons, all activities in the RCA clean procedure should be performed in a Clean Station Work Area which is located under an exhaust fume hood.
[Figure 1] RCA cleaning
the RCA clean proceedure consists of the following steps
: Chemical Storage ⇒ Mix Organic Solution ⇒ Mix Ionic Solution ⇒ Mix HF Solution ⇒ Set-Up Bubbler Rinse
materials to be used in processing for CMOS devices
Process compatibility - for one, the film must survive sufficiently hightemperatures such as a Rapid thermal anneal to 1000 °C for say, 10 s (as dictated by the CMOS technological process)
Reliability
Stability against degradation by the electric field and injected carriers.
Precursor availability
Precursor and process costs
Fracture
Static Loading
Brittle, Ductile, Creep Rupture
Fatigue(Dynamic Loading)
A degradation of mechanical properties leading to failure
of a material or a component under cyclic loading
High/Low cycle, Fatigue crack growth
Classification of failures according to cause
77% of failures are
generally caused
directly or indirectly
by fatigue
Process of fatigue fracture
The
design
③Mixing the cement
④Produce specimen
⑤Humidity curing
Ⅱ. test description
① Grind the specimen surface
② Strain Gage establishment
③ Measuring creep and shrinkage
④ Measuring strength
◎ Tension strength
- Theoretical value: => 2.12MPa< <3.45MPa, =27.6
- Experimental value:
■ Result discussion
High content of water caused lower strength
Figure 13 shows that cryo pump is cooling pump. It means this pump is cooling, liquefaction and store air, not pumping. Generally, it has 3 processes like condensation, absorption and trap at low temperature. The cooled air or molecules do not have any momentum so it is no possibility to heat any molecules. It means vacuum.
Cryo pump have High emission velocity and high emission capacity so it