Process parameters in melting experiment of nodular cast iron

During the sample preparation of nodular cast iron, the discharge temperature, pouring temperature, spheroidizing treatment time and total pouring time of nodular cast iron were measured on the experimental site. The measurement results are shown in the table.

From the measured process parameters of nodular cast iron, it can be seen that the great difference in the weight of molten iron between Series A and Series B will lead to different drop rates of temperature during spheroidization reaction. Therefore, the discharge temperature of series a is higher than that of Series B to ensure the consistency of pouring temperature. A1 has a higher discharge temperature of 1536 ℃, which exceeds the 1450-1520 ℃ set by the experiment. The pouring temperature of A2 at 1321 ℃ is low, which is lower than 1350-1390 ℃.

Number	Toutput / ℃	Tpouring / ℃	ΔT/℃	t-reaction / S	t-total
A1	1536	1389	147	84	9 minutes 18 seconds
A2	1495	1321	174	115	10 minutes 17 seconds
A3	1472	1360	112	80	9 minutes 40 seconds
A4	1468	1355	113	102	8 minutes 50 seconds
A5	1510	1383	127	110	9 minutes 30 seconds
A6	1505	1354	151	117	9 minutes 40 seconds
A7	1510	1347	163	120	9 minutes 40 seconds
A8	1465	1374	91	101	10 minutes 50 seconds
B1	1450	1373	77	127	15 minutes 48 seconds
B2	1460	1390	70	60	12 minutes 20 seconds
B3	1454	1386	68	68	12 minutes 04 seconds
B4	1460	1389	71	94	12 minutes 59 seconds

The reaction time of series a is long and the reaction speed is slow, while that of Series B is fast, but the total time is long. Therefore, under the condition of little difference in discharge temperature, the spheroidization reaction speed of nodular cast iron is closely related to the amount of molten iron used in the reaction. The amount of molten iron used in the spheroidization reaction of nodular cast iron is large, the reaction speed is fast and the reaction time is short. On the contrary, when the amount of molten iron used in the spheroidization reaction is small, the reaction speed is slow, The reaction time is longer.

Judging from the experimental data, the melting process parameters in the nodular cast iron experiment are basically stable, the overall level meets the requirements formulated before the experiment, and the melting process parameters formulated in the nodular cast iron experiment are reasonable.