Study On Thermal Analysis Of High Creep Rated Compacted Graphite Iron

The trend of Heavy-duty automobile engine cylinder block cylinder head material is lightweight thin-walled, saving raw materials, save fuel and reduce pollution emissions, and increase its service life. Compared with ductile cast iron, compacted graphite iron have the same intensity, and it compared with gray cast iron, also have the same as the it shock absorption, thermal properties and casting properties, but the toughness and fatigue resistance of compacted graphite iron is higher than gray cast iron, so it is suitable for the engine cylinder head material.As iron cylinder block material, compacted graphite iron require its creep rate of 80%to play its best performance. Thermal analysis techniques of comp-acted graphite iron melt state evaluation is compacted graphite iron cylinder m ass production of key technologies. This paper combines research Jiangling Foundry compacted graphite iron cylinder block to carry out test by using therm-al analysis, thermal analysis sample homemade cup, use the factory’s original h-ot metal, creep agent, inoculant, the ball like raw materials, conducting many experiments accomplish a database of between metallurgical and thermal analys is and nodularity. To characterize the melt mass of compacted graphite iron, we use thermal analysis the characteristic values a nd the overall shape of the thermal analysis sample cup under solidification segment of solidification con-ditions. By combining the accomplished database, instead of the traditional linear regression or non-linear approximate on method to identify compacted graphite iron melt state, it achieves a fast and accurate evaluation of compacted graphite iron melt state.By adding different amounts of creep agent, inoculant, the ball and the li-ke, our preliminary results is that the graphite shape has a close relationship between the value of the thermal analysis curves’ lowest eutectic temperature and eutectic TEU maximum temperature TER: when TEU more than 1143 ℃, TER more than 1153 ℃, the graphite is flake, which is the gray iron; when TEU between 1130℃ and 1143℃, TER between 1150℃ and 1153℃, the graphit-e is a worm and ≤50% ductile, which is compacted graphite iron; when TEU between 1130℃ and 1143℃, TER between 1143℃ and 1150℃, the graphite is worms and > 50% ductile, which is ductile iron. Combined with the overall shape of the entire thermal analysis to determine the graphite morphology, preliminary result is that when integrated parameter M less than 10, the shape substantially similar thermal analysis, graphite morphology similar.Ti also carried out late on the ball of the nodularity impact test, Ti is a kind of antiball elements, can reduce the residual amount of hot metal ball el-ements of graphite worms. Preliminary results; With increasing Ti content, the ball of tissue sample rate increased first downward trend, and when the additi-on amount of Ti ball at the highest rate of 0.0595 percent, the lowest rate of creep, continue to add Ti ball rate downward trend.