RU2469517C1 RU2011122433/07A RU2011122433A RU2469517C1 RU 2469517 C1 RU2469517 C1 RU 2469517C1 RU 2011122433/07 A RU2011122433/07 A RU 2011122433/07A RU 2011122433 A RU2011122433 A RU 2011122433A RU 2469517 C1 RU2469517 C1 RU 2469517C1 Authority RU Russia Prior art keywords electrode plasma gas heat arc Prior art date Application …