  The short-lived $^{182}$Hf-$^{182}$W decay system is a powerful chronometer
for constraining the timing of metal-silicate separation and core formation in
planetesimals and planets. Neutron capture effects on W isotopes, however,
significantly hamper the application of this tool. In order to correct for
neutron capture effects, Pt isotopes have emerged as a reliable in-situ neutron
dosimeter. This study applies this method to IAB iron meteorites, in order to
constrain the timing of metal segregation on the IAB parent body. The
$\epsilon^{182}$W values obtained for the IAB iron meteorites range from -3.61
$\pm$ 0.10 to -2.73 $\pm$ 0.09. Correlating $\epsilon^{\mathrm{i}}$Pt with
$^{182}$W data yields a pre-neutron capture $^{182}$W of -2.90 $\pm$ 0.06. This
corresponds to a metal-silicate separation age of 6.0 $\pm$ 0.8 Ma after CAI
for the IAB parent body, and is interpreted to represent a body-wide melting
event. Later, between 10 and 14 Ma after CAI, an impact led to a catastrophic
break-up and subsequent reassembly of the parent body. Thermal models of the
interior evolution that are consistent with these estimates suggest that the
IAB parent body underwent metal-silicate separation as a result of internal
heating by short-lived radionuclides and accreted at around 1.4 $\pm$ 0.1 Ma
after CAIs with a radius of greater than 60 km.
