Dear Friend,
Bond is nothing but a Indemnity Contract under Contract Act and breach of it is hit by Section 73 to 75 of the Contract Act.
The Company can file civil case against you for breach of such contract and ask you to indemnify the losses incurred by it cause of your breach, such calculation of losses cannot be remote losses but yes it may include Air fare and visa charge, Allowance paid in abroad for food and living, Medical insurance cost in abroad, Boarding and lodging cost.
The company can also take action under criminal laws but the same are frivolous and may not be subsist.
What defence you can take is the Bond is one-sided and you may have signed in undue influence but the same are very tough to proof and only good lawyer can handle such defence. Your lawyer may take defence of signing the bond on Rs50/- Stamp paper, i think it should be Rs100/-(may be the State Acts varies)
Further, it is to be noted that your bond may have Arbitration Clause and you can initiate concilliation to settle the issue ammicably with your company.
Hope this helps... Regards