chapterheads_mats.sty

\def\@makechapterhead#1{%
  \vspace*{50\p@}%
  {\parindent \z@ \raggedright \normalfont
    \ifnum \c@secnumdepth >\m@ne
          \HUGE \thechapter \space #1\par\nobreak
    \vskip 40\p@
    \fi
    \interlinepenalty\@M
  }}

\def\@makeschapterhead#1{%
  \vspace*{50\p@}%
  {\parindent \z@ \raggedright
    \normalfont
    \interlinepenalty\@M
    \HUGE #1\par\nobreak
    \vskip 40\p@
  }}

\def\HUGE{\fontsize{30}{48pt}\selectfont}