en Research Paper Research Paper <span style="font-size:11pt"><span style="line-height:115%"><span calibri="" style="font-family:"><span style="font-size:12.0pt"><span style="line-height:115%"><span new="" roman="" style="font-family:" times="">Pressureless sintering was employed at 1400 &deg;C to synthesize Ti matrix composites (TMCs) reinforced with in-situ TiB and TiC reinforcements using TiB₂ and B₄C initial reinforcements. The microstructure and wear behavior of the synthesized composites were evaluated and compared and </span></span></span><span style="font-size:12.0pt"><span style="line-height:115%"><span new="" roman="" style="font-family:" times="">the results showed that B₄C caused the formation of TiB-TiC in-situ hybrid reinforcements in the Ti matrix. Also, TiB was in the form of blades/needles and whiskers, and TiC was almost equiaxed. Moreover, </span></span></span><span style="font-size:12.0pt"><span style="line-height:115%"><span new="" roman="" style="font-family:" times="">the volume fraction of the in-situ formed reinforcement using B₄C was much higher than that formed using </span></span></span><span style="font-size:12.0pt"><span style="line-height:115%"><span new="" roman="" style="font-family:" times="">TiB₂</span></span></span><span style="font-size:12.0pt"><span style="line-height:115%"><span new="" roman="" style="font-family:" times="">. In addition, although the hardness of the B₄C-synthesized composites was higher, the composite synthesized using 3 wt.% TiB₂ exhibited the highest hardness </span></span></span><span style="font-size:12.0pt"><span style="line-height:115%"><span new="" roman="" style="font-family:" times="">(425 HV)</span></span></span><span style="font-size:12.0pt"><span style="line-height:115%"><span new="" roman="" style="font-family:" times="">. The wear test results showed that the sample synthesized using 3 wt.% TiB₂ showed the lowest wear rate at 50 N, mainly because of its higher hardness. The dominant wear mechanism in the samples synthesized using 3 wt.% B₄C was abrasive and delamination at 50 N and 100 N, respectively while in the samples synthesized 3 wt.% TiB₂, a combination of delamination and adhesive wear and adhesive wear was ruling, respectively.</span></span></span></span></span></span><br> <br> &nbsp; Pressureless sintering,Titanium,Composite,Microstructure,Wear 118 131 http://ijmse.iust.ac.ir/browse.php?a_code=A-10-5224-1&slc_lang=en&sid=1 Alireza Zibanejad-rad alirezazibanejadrad@gmail.com 1800319475328460020125 1800319475328460020125 No Faculty of Materials & Manufacturing Processes, Malek Ashtar University of Technology, Babaei Highway, Shabanloo Street, Tehran, Iran Ali Alizadeh alizadehh53@gmail.com 1800319475328460020126 1800319475328460020126 Yes Faculty of Materials & Manufacturing Processes, Malek Ashtar University of Technology, Babaei Highway, Shabanloo Street, Tehran, Iran Seyyed Mehdi Abbasi sma.abbasi955@gmail.com 1800319475328460020127 1800319475328460020127 No Metallic Materials Research Center, Malek Ashtar University of Technology, Babaei Highway, Shabanloo Street, Tehran, Iran