main purpose SKD61
Suitable for making aluminum, zinc and copper alloy extrusion die casting, forging and pressing and hot, hot cutting blades, etc, is the ideal, plunger, also suitable for material of plastic mold manufacturing high yield
Most.
Steel specialty
Good toughness and high temperature resisting fatigue, can withstand the temperature, temperature in the fusion for long-term job with good cutting performance and polishing performance.
Heat treatment process
1) preheating temperature: for 600-630 degrees Celsius, holding time for 1.5-2. Oh (depending on the mold size), then up to 830-850 ° c, 1.5-2. Oh. This process is quenched
Before the pretreatment, it can adjust workpiece microstructure defects, internal to the necessary conditions for the quenching.
2) in the pretreatment of quenching: based on the heating temperature, to 10.4 degrees, the insulation 1080-2-2.5 h, DaiGong thing from oil quenching temperature dropped to 130 degrees Celsius removed from oil
Cold.
3) : hardened piece.it inside mould has bigger stress, must be in 1 ~ to work within the 2h, in order to eliminate hardened piece.it stress. In order to avoid cracking, return
Before the fire shall also heating and specific methods for: the piece to 380-400 degrees Celsius heat insulation 1 hour again slowly warming to 58-600℃ for a tempering, holding time for 2. Oh,
Then come to the temperature of cold air after a second temper, tempering for 560-5.8 degrees Celsius temperature, holding time, then baked for 2h air-cooling.
In view of the above, the need to add heat treatment process was H13R: because 4Cr5MoSiVI (to) steel quenching temperature sensitive (pictured above), and under high temperature quenching excellent performance
With its practice, so high temperature quenching.
4) nitriding: 525 degrees soft nitriding process, surface hardness can achieve 1000-1250HV nitriding time 20 hours 30 hours 60 hours hardening layer respectively 0.20 mm depth
Mm, 0.25 mm, 575 degrees Celsius, 0.30 soft nitriding process, working surface hardness is about 950HV. Usually soft nitriding process 2 hours, hardening layer depth 20um - 10.