Details

Autor(en) / Beteiligte

• Fang, J.X.
• Li, S.B.
• Dong, S.Y.
• Wang, Y.J.
• Huang, H.S.
• Jiang, Y.L.
• Liu, B.

Titel

Effects of phase transition temperature and preheating on residual stress in multi-pass & multi-layer laser metal deposition

Ist Teil von

• Journal of alloys and compounds, 2019-07, Vol.792, p.928-937

Ort / Verlag

Lausanne: Elsevier B.V

Erscheinungsjahr

2019

Quelle

Access via ScienceDirect (Elsevier)

Beschreibungen/Notizen

• To investigate the influences of phase transition temperature and preheating on the residual stress of multi-layer and multi-pass laser metal deposition (LMD), the multi-layer and multi-pass LMD, with and without preheating, were performed using five kinds of alloy with different phase transition features, and their residual stresses were measured using the hole drilling method. A finite-element (FE) model incorporating the phase transition was developed based on experimentally obtained physical property data. The results demonstrated that the low-temperature solid phase transition has a tensile stress relaxation effect, which leads to the formation of a compressive stress area. This relaxation effect was observed to decrease with the increase of the phase transition temperature. The high-temperature solid phase transition has no significant tensile stress relaxation effect during the multi-layer and multi-pass LMD process, which is different from the single track LMD. when the solid phase transition temperature is low, the preheating can improve the uniformity of the stress field only to a certain extent. However, when the preheating increases the lowest temperature of the thermal cycle and makes it higher than the starting point temperature of the solid phase transition, the tensile stress relaxation effect of the solid phase transition can be brought into full play. •FE model considering phase transition based on testing data of physical property.•The influences of the stress on phase transition kinetics and TRIP are considered.•Tensile stress relaxation effect (TSRE) decreases as phase transition temp rises.•TSRE of high-temp phase transition could be brought into full play by preheating.