Wire + Arc Additive Manufacturing and Heat Treatment of Super Martensitic Stainless Steel with a Refined Microstructure and Excellent Mechanical Properties.

Due to the advantages of relatively low cost, increased energy efficiency, increased deposition rate, and the capacity to create medium to large scale components, wire + arc additive manufacturing (WAAM) has gained growing interest. Super martensitic stainless steel (SMSS) combines outstanding strength, ductility, and corrosion resistance, making it a great option for WAAM. In the present work, an SMSS component was successfully produced by WAAM.

Microstructure Evolution and Mechanical Properties of Underwater Dry and Local Dry Cavity Welded Joints of 690 MPa Grade High Strength Steel.

Q690E high strength low alloy (HSLA) steel plays an important role in offshore structures. In addition, underwater local cavity welding (ULCW) technique was widely used to repair important offshore constructions. However, the high cooling rate of ULCW joints results in bad welding quality compared with underwater dry welding (UDW) joints.

catena-Poly[[[diaqua-cobalt(II)]bis-(μ-1,3-di-4-pyridylpropane-κN:N')] bis-(perchlorate) bis-(1,3-di-4-pyridyl-propane) bis-(2-methyl-4-nitro-aniline)].

In the title compound, {[Co(C(13)H(14)N(2))(2)(H(2)O)(2)](ClO(4))(2)·2C(13)H(14)N(2)·2C(7)H(8)N(2)O(2)}(n), the Co(II) ion lies on a crystallographic inversion center and is coordinated by four N atoms from four symmetry-related 1,3-di-4-pyridylpropane ligands and two O atoms from two water ligands in a slightly distorted octa-hedral coordination environment. The 1,3-di-4-pyridylpropane ligands are doubly bridging and connect the Co(II) ions into one-dimensional chains. The asymmetric unit also contains one uncoordinated 1,3-di-4-pyridylpropane mol-ecule, one 2-methyl-4-nitro-aniline mol-ecule and one perchlorate anion.