Yes, MIL-STD-202F is good testing condition for bare PCB. But I look up IPC-TM-650 to find thermal cycling condition. It is as same as MIL's but qualification criteria is different. Which should I follow? Do you think it is possibleto satisfy the requirement of FR-4 thermal shock according to IPC-TM-650 if I use air to air chamber? Howard Lin Maxedge RD Center > -----Original Message----- > From: Werner Engelmaier [SMTP:[log in to unmask]] > Sent: Wednesday, August 26, 1998 10:48 AM > To: [log in to unmask] > Subject: Re: [TN] Thermal Cycling > > Hi Howard, > It depends what it is you want to be doing. MIL-STD-202F thermal > cycling was > fine for hybrid assemblies or bare PCBs, but a disaster for SM > assemblies, > because it was outside the temperature ranges for near linear > temperature- > dependent property changes. For SM assemblies look at IPC-SM-785. > > Werner Engelmaier > Engelmaier Associates, L.C. > Electronic Packaging, Interconnection and Reliability Consulting > 7 Jasmine Run > Ormond Beach, FL 32174 USA > Phone: 904-437-8747, Fax: 904-437-8737 > E-mail: [log in to unmask] > > ################################################################ > TechNet E-Mail Forum provided as a free service by IPC using LISTSERV > 1.8c > ################################################################ > To subscribe/unsubscribe, send a message to [log in to unmask] with > following text in the body: > To subscribe: SUBSCRIBE TechNet <your full name> > To unsubscribe: SIGNOFF TechNet > ################################################################ > Please visit IPC's web site (http://www.ipc.org) "On-Line Services" > section for additional information. > For technical support contact Hugo Scaramuzza at [log in to unmask] or > 847-509-9700 ext.312 > ################################################################ ################################################################ TechNet E-Mail Forum provided as a free service by IPC using LISTSERV 1.8c ################################################################ To subscribe/unsubscribe, send a message to [log in to unmask] with following text in the body: To subscribe: SUBSCRIBE TechNet <your full name> To unsubscribe: SIGNOFF TechNet ################################################################ Please visit IPC's web site (http://www.ipc.org) "On-Line Services" section for additional information. For technical support contact Hugo Scaramuzza at [log in to unmask] or 847-509-9700 ext.312 ################################################################