Eng
Ukr
Rus
Print
2017 №09 (10) DOI of Article
10.15407/as2017.09.01
2017 №09 (02)

Automatic Welding 2017 #09
Avtomaticheskaya Svarka (Automatic Welding), #9, 2017, pp. 3-9
Influence of the ratio of dynamic and static stresses on brittle fracture resistance of low-alloyed steel welded joints


 
 
Authors
V.A. Degtyarev
G.S. Pisarenko Institute for Problems of Strength, NASU 2 Timiryazevskaya Str., 01014, Kiev-14, Ukraine. E-mail: ips@ipp.kiev.ua
 
Abstract
Results of experimental studies of the influence of the ratio of static and dynamic stresses on limit stresses and second critical brittleness temperature of butt welded joints with a crack on 09G2 and 12GN2MFAYu steels under the conditions of room and low (to –80 °C) temperatures are analyzed. It is found that at the specified temperature the dynamic component of critical stress decreases linearly with increase of static stress. It is shown that decrease of limit stresses and increase of the second critical brittleness temperature take place at increase of the dynamic factor. Critical brittleness temperatures of welded joints of steel with higher mechanical properties are significantly lower. It is found that ignoring the dynamic stresses leads to underestimated values of limit stress and overestimated values of second critical brittleness temperature. Presented analysis of research allows a more substantiated approach to assessment of brittle fracture resistance of structural elements made from the studied materials, and determination of their safety margins. 7 Ref., 1 Table, 7 Figures.
Keywords: welded joint, critical brittleness temperature, limit stress diagram, yield point
 
Received:                23.05.17
Published:               10.10.17
 
 
References
  1. Grigoriev, R.S., Larionov, V.P., Urzhumtsev, Yu.S. (1987) Methods of increase of serviceability of equipment in North version. Novosibirsk: Nauka. Siberian section.
  2. Telushkin, V.D., Vinokurov, V.A., Ryakhin, V.A. et al. (1978) Road-building machines for regions with cold climate. Moscow: Mashinostroenie.
  3. Sleptsov, O.I., Shulginov, B.S., Mikhajlov, V.E. et al. (2012) Improvement of strength of welded metal structures of mining and transport engineering under conditions of North. Novosibirsk: Nauka.
  4. Makhutov, N.A. (1973) Resistance of structure elements to brittle fracture. Moscow: Mashinostroenie.
  5. Trufyakov, V.I. (1973) Fatigue of welded joints. Kiev: Naukova Dumka.
  6. (1985) GOST 25.506–85: Methods of mechanical tests of metals. Determination of characteristics of crack resistance (fracture toughness) under static loading. Moscow: Standart.
  7. Degtyaryov, V.A. (1982) Units of DSO type for fatigue testing under repeated impact loading with different cycle asymmetry. Problemy Prochnosti, 10, 110–113.

>