Effect of heat treatment on microstucture and properties of explosive welding clad plate of TA1/Q345

The composite plate made by explosion welding technology generally has high residual stress and bed plasticity due to the explosion reinforcement. The heat treatment can play a part of eliminating stress and recovering property.In this study,TA1/Q345 clad plate made by explosive welding was annealed at different temperatures.The microstructure,micro-hardness,and tensile,shear,and bending properties were analyzed after anneal.The result shows that there is fibrous structure in the bonding zone and the plastic deformation is severe,the grain growth and fibrous structure dribbles away with the temperature increasing.Micro-hardness in the interface is bigger than it on the both sides. Tensile and shear strength reduced with the temperature of heat treatment increasing.The propel anneal temperature for TA1/Q345 clad plate is 600

Microstructure and properties of S30403+Q345R roll-bonded clad steel plate for pressure vessels

To meet the demand of the domestic pressure vessel industry for roll-bonded clad steel plates, Baosteel has developed an S30403 ＋ Q345R roll-bonded clad steel plate. Comprehensive inspections of the composition, microstructure, and properties are made to systematically evaluate the steel plate in the normalized and normalized ＋ stress relieved states. The results show the cladding interface of the S30403 ＋ Q345R roll-bonded clad steel plate has high shear strength, the base metal has good properties, and the mechanical properties of the steel plate head and tail are uniform. The performance is fully consistent with the technical requirements of the roll-bonded clad steel plate for pressure vessels.

Effect of Reduction on Bonding Interface of Hot-rolled Wear-resistant Steel BTW1/Q345R Cladding Plate

Wear-resistant cladding plates consisting of a substrate（Q345 R） and a clad layer（BTW1） were bonded through hot rolling at the temperature of 1 200 ℃ and a rolling speed of 0.5 m/s. The microhardness of the cladding plate was also tested after being heat treated. The microstructure evolution on the interface of BTW1/Q345 R sheets under various reduction rates was investigated with a scanning electron microscope（SEM） and EBSD. It is found that the micro-cracks and oxide films on the interface disappear when the reduction is 80%, whereas the maximum uniform diffusion distance reaches 10 μm. As a result, a wide range of metallurgical bonding layers forms, which indicates an improved combination between the BTW1 and the Q345 R. Additionally, it is discovered that the unbroken oxide films on the interface are composed of Mn, Si or Cr at the reductions of 50% and 65%. The SEM fractography of tensile specimen demonstrates that the BTW1 has significant dimple characteristics and possesses lower-sized dimples with the increment in reduction, suggesting that the toughness and bonding strength of the cladding plates would be improved by the increase of reduction. The results reveal that a high rolling reduction causes the interfacial oxide film broken and further forms a higher-sized composite metallurgical bonding interface. The peak microhardness is achieved near the interface.

2种终轧/开冷温度DSS 2304复合板复层组织与耐腐蚀性能对比研究

目的 对比研究2种不同终轧/开冷温度的2304/Q345C热轧双相不锈钢复合板复层组织和耐腐蚀性能。方法 分别采用金相显微镜和透射电镜观察复层组织形貌,采用铁素体测量仪分析计算复层远界面铁素体组织。分别采用化学浸泡法及电化学法测试复层抗点蚀和晶间腐蚀性能,并对其组织进行金相观察和透射分析。采用万能试验机对界面进行剪切强度测试,对界面附近进行线扫描测试分析,进一步分析剪切性能测试结果。结果 在其他热轧参数一定的情况下,终轧/开冷温度为1050/1020℃的复合板复层组织中的铁素体含量较高,奥氏体/铁素体相界更为规整,位错密度较低,晶界未发现析出相,界面剪切强度较高,复层的耐点腐蚀、晶间腐蚀及腐蚀电化学性能均较优。结论 终轧/开冷温度为1050/1020℃的热轧双相不锈钢复合板复层具有更优的耐腐蚀性能。