Electronics Forum | Wed May 09 17:13:06 EDT 2007 | zanolli
Re: 63/37 paste reflow Is there a standard reccomended time (ball park) above liquidus? What are the negative ramifications if the TAL is too short or too long? Thanks in advance
Electronics Forum | Fri May 25 13:38:15 EDT 2007 | mfgengr
TAL Too Long - dull solder joints, dewetting. TAL Too Short - cold solder, insufficient wetting. You want TAL to be as short as possible (but not lower than 30 seconds), but long enough for every solder joint to be above TAL for at least 30 seconds.
Industry News | 2018-10-18 08:44:36.0
Lead-free Reflow Profile: Soaking type vs. Slumping type
Industry News | 2018-10-18 10:18:58.0
Case study: How to Create a Reflow Profile for a 16-layer, 2mm Thickness PCB with a High Density SMT Connector?
Technical Library | 2023-01-17 17:27:13.0
Reflow profile has significant impact on solder joint performance because it influences wetting and microstructure of the solder joint. The degree of wetting, the microstructure (in particular the intermetallic layer), and the inherent strength of the solder all factor into the reliability of the solder joint. This paper presents experimental results on the effect of reflow profile on both 63%Sn 37%Pb (SnPb) and 96.5%Sn 3.0%Ag 0.5%Cu (SAC 305) solder joint shear force. Specifically, the effect of the reflow peak temperature and time above solder liquidus temperature are studied. Nine reflow profiles for SAC 305 and nine reflow profiles for SnPb have been developed with three levels of peak temperature (230 o C, 240 o C, and 250 o C for SAC 305; and 195 o C, 205 o C, and 215 o C for SnPb) and three levels of time above solder liquidus temperature (30 sec., 60 sec., and 90 sec.). The shear force data of four different sizes of chip resistors (1206, 0805, 0603, and 0402) are compared across the different profiles. The shear force of the resistors is measured at time 0 (right after assembly). The fracture surfaces have been studied using a scanning electron microscopy (SEM) with energy dispersive spectroscopy (EDS)
Technical Library | 2007-12-20 16:28:08.0
Despite much research and discussion on the subject of reflow profiling, many questions and a good deal of confusion still exist. What is clear is that the pains often associated with profiling can be reduced if there is a strong understanding of the variables that can be encountered during the reflow process, as well as the metallurgical dynamics of the soldering process. This paper shall provide a brief outline of the reflow profile in general, with specific emphasis placed upon the suggested time spent above the melting temperature of the solder. The guidelines for soldering to various surfaces and with alternative solder alloys also are discussed.
Events Calendar | Thu Oct 03 00:00:00 EDT 2019 - Thu Oct 03 00:00:00 EDT 2019 | ,
IPC Tech Ed Webinar Series: Ball Grid Array (BGA) and Bottom Termination Component (BTC) Design and Assembly Challenges: Reflow Profiling to Achieve Low Defect Rates and Successful Assembly! – Part 2
Reflow Profiling: Time Above Liquidus Reflow Profiling: Time Above Liquidus Despite much research and discussion on the subject of reflow profiling, many questions and a good deal of confusion still exist. What is clear is that the pains often
Heller Industries Inc. | https://hellerindustries.com/wp-content/uploads/2018/07/pan_APEX06.pdf
. Research studies show that the peak temperature (PT) and time above liquidus (TAL) during the reflow process are the most critical parameters, impacting solder joints reliability (Arra, 2002; Salam, et al., 2004
